Silverlight 2.0: usage of the converters from external assembly in app.xaml

Hi all,
it is my first post and I'd like to strat it from a small trick for defining value converters in app.xaml file in silverlight project.
Problem:
If you define Converters in app.xaml (see below) then you find that Visual Studio designer fails to render User Controls (Visual Studio designer become blank).

Upd: not the converter defenition in app.xaml file cause the visual studio designer to go blank but xmlns defenition.
Solution:

To avoid this designer problem move namespace declaration closer to usage:


Voila!!! now designer work perfect and able to render our content.

http://blog.andrew-veresov.com/post/Silverlight-20-usage-of-the-converters-from-external-assembly-in-appxaml.aspx

What’s new in .NET Framework 4.0

· Next versions of Windows Communication Foundation (WCF) and Windows Workflow Foundation (WF) will provide better support for Web 2.0 technologies like REST, POX, ATOM.
· Performance and Scalability of WCF and WF are expected to increase by minimum 10X.
· New workflow models.
· Seamless integration between WCF and WF including a new Visual Designer.
· Parallel Programming framework using PLINQ, Task Parallel Library and Coordination Data Structures to better utilize power of multi-processor and multi-core machines.
· Build declarative applications with WF, WCF and WPF using XAML. So, XAML is no more only for WPF and WF.
· WCF enhancements :
o RESTful enhancements
§ Simplifying the building of REST Singleton & Collection Services, ATOM Feed and Publishing Protocol Services, and HTTP Plain XML Services using WCF
§ WCF REST Starter Kit to be released on Codeplex to get early feedback
o Messaging enhancements
§ Transports - UDP, MQ, Local in-process
§ Protocols - SOAP over UDP, WS-Discovery, WS-BusinessActivity, WS-I BP 1.2
§ Duplex durable messaging
o Correlation enhancements
§ Content and context driven, One-way support
o Declarative Workflow Services
§ Seamless integration between WF and WCF and unified XAML model
§ Build entire application in XAML, from presentation to data to services to workflow
· WF enhancements :
o Significant improvements in performance and scalability
§ Ten-fold improvement in performance
o New workflow flow-control models and pre-built activities
§ Flowcharts, rules
§ Expanded built-in activities – PowerShell, database, messaging, etc.
o Enhancements in workflow modeling
§ Persistence control, transaction flow, compensation support, data binding and scoping
§ Rules composable and seamlessly integrated with workflow engine
o Updated visual designer
§ Easier to use by end-users
§ Easier to rehost by ISVs
§ Ability to debug XAML
· First CTP to be released during PDC in Oct 2008.
· Information on this page will be updated as and when it is available.
.stylebak1 {
background-color:silver;
}
.style2 {
text-align: left;
font-family: Verdana;
}
.style3 {
text-align: left;
font-family: Arial, Helvetica, sans-serif;
}
.style4 {
color: #FFFFFF;
background-color: #000000;
}
Related Articles
Parallel Computing using .NET framework - Overview
Master Managed Threading and Synchronization Techniques

Creating Virtual directory in IIS with c#

///

/// Creates the virtual directory. ///

/// The web site. /// Name of the app. /// The path. /// /// Exception. public static bool CreateVirtualDirectory(string webSite, string appName, string path) { var schema = new DirectoryEntry("IIS://" + webSite + "/Schema/AppIsolated"); bool canCreate = !(schema.Properties["Syntax"].Value.ToString().ToUpper() == "BOOLEAN"); schema.Dispose(); if (canCreate) { bool pathCreated = false; try { var admin = new DirectoryEntry("IIS://" + webSite + "/W3SVC/1/Root"); //make sure folder exists if (!Directory.Exists(path)) { Directory.CreateDirectory(path); pathCreated = true; } //If the virtual directory already exists then delete it IEnumerable matchingEntries = admin.Children.Cast().Where(v => v.Name == appName); foreach (DirectoryEntry vd in matchingEntries) { admin.Invoke("Delete", new[] { vd.SchemaClassName, appName }); admin.CommitChanges(); break; } //Create and setup new virtual directory DirectoryEntry vdir = admin.Children.Add(appName, "IIsWebVirtualDir"); vdir.Properties["Path"][0] = path; vdir.Properties["AppFriendlyName"][0] = appName; vdir.Properties["EnableDirBrowsing"][0] = false; vdir.Properties["AccessRead"][0] = true; vdir.Properties["AccessExecute"][0] = true; vdir.Properties["AccessWrite"][0] = false; vdir.Properties["AccessScript"][0] = true; vdir.Properties["AuthNTLM"][0] = true; vdir.Properties["EnableDefaultDoc"][0] = true; vdir.Properties["DefaultDoc"][0] = "default.aspx,default.asp,default.htm"; vdir.Properties["AspEnableParentPaths"][0] = true; vdir.CommitChanges(); //the following are acceptable params //INPROC = 0, OUTPROC = 1, POOLED = 2 vdir.Invoke("AppCreate", 1); return true; } catch (Exception) { if (pathCreated) Directory.Delete(path); throw; } } return false; }

Important URLs

http://www.topxml.com/XML/re-39078_Recipe--Dynamic-Site-Layout-and-Style-Personalization-with-ASP-NET.aspx
http://www.brainbell.com/tutorials/ASP/Using_Personalization.html
http://www.webreference.com/programming/asp/site_appearance3/2.html


JavaScript:
http://it.toolbox.com/blogs/coding-dotnet/validation-of-date-using-javascript-18023
http://www.aspdotnetcodes.com/ViewQuestion_161.aspx
weschools.com

jQuery Tutorials for Designers
http://www.webdesignerwall.com/tutorials/jquery-tutorials-for-designers/

LINQ URL
http://csainty.blogspot.com/2008/01/linq-to-sql-insertupdatedelete.html
http://www.codeproject.com/KB/linq/LINQSQLCS.aspx
http://www.aspnettutorials.com/tutorials/database/linq-adding-database-ajax-cs.aspx
http://69.10.233.10/KB/WPF/binding_in_linq-sql.aspx?display=Print
http://www.c-sharpcorner.com/UploadFile/scottlysle/GenericL2SinCS07212008041344AM/GenericL2SinCS.aspx

SharePoint Interview Question URL
http://www.megasolutions.net/qs/Sharepoint_Portal_Interview_Questions.aspx

SQL Server URL
http://sqltips.wordpress.com/category/row_number/

http://www.blogtoplist.com/software/blogdetails-11403-3.html

http://database.ittoolbox.com/documents/popular-q-and-a/how-to-find-the-nth-maxmin-records-in-sql-server-2803

http://www.sqlteam.com/article/find-nth-maximum-value-in-sql-server


http://www.planet-source-code.com/URLSEO/entrancegeneric/ShowWorldSeOnly!asp/blnResetAllVariables!False/intFirstRecordOnPage!1/intLastRecordOnPage!20/intLastRecordInRecordset!5806/cmdGoToPage!2/lngWId!10/anyname.htm


http://www.geekpedia.com/tutorial181_Capturing-screenshots-using-Csharp.html

http://www.codeproject.com/KB/aspnet/NTierApp_UsingLINQ.aspx

http://www.hookedonlinq.com/StandardQueryOperators.ashx


One More for AJAX
http://www.worldofasp.net/News/AJAX/re-2747_How-to----move-from-AjaxPro-to-ASP-NET-AJAX-PageMethods.aspx

http://www.asp.net/ajax/documentation/live/tutorials/ExposingWebServicesToAJAXTutorial.aspx


Microsoft's founder and head Bill Gates steps down
http://www.microsoft.com/presspass/exec/billg/videos/default.aspx?videoID=0

Tired of querying in antiquated SQL?
http://linqpad.net/

Create Data-Centric Web Applications With Silverlight 2
http://msdn.microsoft.com/hi-in/magazine/cc895493(en-us).aspx?pr=blog

Winwodws Workflow Foundation - Good Links
http://joeon.net/post/Windows-Communication-Foundation---65-Links-to-make-you-an-expert!.aspx

http://weblogs.asp.net/scottgu/archive/2006/08/31/windows-workflow-foundation.aspx

http://msdn.microsoft.com/en-us/library/ms734584(VS.85).aspx

http://joeon.net/post/2008/02/Windows-Workflow-Foundation-Tutorial-Series.aspx

SharePoint - Search Link for WSS 3.0 & MOSS 2007
http://msdnrss.thecoderblogs.com/2008/09/16/spsearchasmx-web-service-will-not-return-any-results-in-the-search-server-2008-integrated-wss-30-environment/
http://sharepointmagazine.net/news/analysis/leveraging-the-sharepoint-platform-part-1

http://sharepointmagazine.net/news/analysis/leveraging-the-sharepoint-platform-part-1



Data Access Tutorials http://www.asp.net/learn/data-access/

SharePoint Reference Site URL
http://laflour.spaces.live.com/
http://msdn.microsoft.com/en-us/library/bb386295.aspx
http://www.google.com/chrome/index.html?hl=en&brand=CHMG&utm_source=en-hpp&utm_medium=hpp&utm_campaign=en

to fetch mails from our pop3 account and store it in db using .net 2.0?
http://www.codeproject.com/KB/IP/Pop3MailClient.aspx

http://microsoft.apress.com/asptodayarchive/72309/listing-all-windows-user-group-accounts-from-asp

SharePoint And Silverlight Integration Presentation Link
http://www.slideshare.net/andynogueira/share-point-summit-2008-andy-nogueira-share-point-and-silverlight
http://www.slideshare.net/andynogueira/share-point-summit-2008-andy-nogueira-share-point-and-silverlight

Silverlight Toolkit URL
http://www.codeplex.com/Silverlight

While in the journey of a fast life, amidst so much competition, anxiety, corporate race, I had a chance to read this. It touched me. So I thought of sharing with you…

CrossTab SQL
http://sqlblogcasts.com/blogs/madhivanan/archive/2007/08/27/dynamic-crosstab-with-multiple-pivot-columns.aspx

Test your web design in different browsers
If you want to test your web application in different browser on different OS, you can use this link (if you do not have systems having different OS and different browser)
http://browsershots.org/

Developing PHP On Your Visual Studio 2008/2005
http://www.dev102.com/2008/09/16/developing-php-on-your-visual-studio-20082005/


SQL URL
http://blogs.msdn.com/lcris/archive/category/12750.aspx


http://www.asp.net/learn/security/view.aspx?__id=05&__language=cs&supportsjs=true

http://quickstarts.asp.net/QuickStartv20/aspnet/doc/security/login.aspx#createuser

Security Basics and ASP.NET Support
http://www.asp.net/Learn/Security/tutorial-01-cs.aspx

Introduction to Web Programming
http://www.microsoft.com/mspress/books/sampchap/6714.aspx

http://support.microsoft.com/kb/178222/en-us

http://support.microsoft.com/kb/162059

Hope you have see this link for Silverlight demo site. Can we plan something like this for a demo site
http://www.mscui.net/PatientJourneyDemonstrator/
http://www.slideshare.net/spushpak/dot-net-training-wcf-dot-net35
Reflection on C# http://basgun.wordpress.com/2008/08/15/virtual-earth-map-control-aspnet/

Remote Desktop Manager using C# - URL
http://www.codeproject.com/KB/cs/Palantir.aspx


Sample Web Application for .NET Clients - URL
http://coherence.oracle.com/display/COH34UG/Sample+Web+Application+for+.NET+Clients

he assembly created from our compiled classes is placed within a subdirectory of
C:\WINDOWS\Microsoft.NET\Framework\VersionNumber\Temporary ASP.NET Files\WebTime
where VersionNumber is the version number of the .NET Framework (e.g., v2.0.50215) installed on your computer.


The below link is for REST
http://weblogs.asp.net/shijuvarghese/archive/2008/04/04/rest-and-wcf-3-5.aspx

URL : FTP, Email, And Threading using C#
FTP C# Examples
http://www.example-code.com/csharp/ftp.asp

Threading in C#
http://www.albahari.com/threading/

Email Object C# Examples
http://www.example-code.com/csharp/emailObject.asp

Workflow Links
http://live.sharepointcommunity.de/wiki/Wiki-Seiten/Workflow.aspx

Threading in C#
http://www.albahari.com/threading/

MOSS Multilingual Site Configuration
http://www.codeproject.com/KB/sharepoint/MOSS_multilingual.aspx

Visual Studio 2008 and .NET Framework 3.5 Training Kit
http://www.microsoft.com/downloads/details.aspx?familyid=8BDAA836-0BBA-4393-94DB-6C3C4A0C98A1&displaylang=en

RSS URL
http://www.mnot.net/rss/tutorial/#What
http://www.rssdotnet.com/documents/code_examples.html
http://cyber.law.harvard.edu/rss/rss.html
http://rss-net.sourceforge.net/documents/class_library_reference/

http://www.dotnetcurry.com/BrowseArticles.aspx?CatID=54&AspxAutoDetectCookieSupport=1

Good Links
http://www.carlosag.net/Tools/CodeTranslator/

http://www.bigresource.com/VB-Get-Internet-Connection-Speed-amp-Bytes-Sent-Received-oilD7D4A9C.html

http://www.bigresource.com/VB-Internet-Connection-Speed-rcZw8KbK70.html



ASP.NET Developer Center
http://msdn.microsoft.com/hi-in/asp.net/default.aspx

Silverlight

http://msdn.microsoft.com/hi-in/silverlight/default(en-us).aspx



Visual Studio 2008 Samples URL
http://msdn.microsoft.com/hi-in/vs2008/bb330936%28en-us%29.aspx

how to Update Multiple rows in sql server table

Hello,

I want to Update Multiple rows in sql server table.

Like Tablename is tblA and I have 2 columns in it id and name

now I want to update more than 1 rows at a time like name=a(id=1),name=b(id=2),name=c(id=3).. and more

let me know the optimized query with example if u can.
Use bulkinsert functionality of sql server 2005

http://develtop.tistory.com/entry/Bulk-Insert-into-SQL-from-C-App


URL : 6 basic steps of how to create a WebPart in SharePoint
http://www.c-sharpcorner.com/UploadFile/shivprasadk/12222301222009065151AM/122223.aspx

http://www.c-sharpcorner.com/UploadFile/sharepointholic/SharePointCustomizationTricks101192009140559PM/SharePointCustomizationTricks1.aspx

http://www.c-sharpcorner.com/UploadFile/mahesh/CustomControls10082008232606PM/CustomControls.aspx


Hope you have see this link for Silverlight demo site. Can we plan something like this for a demo site
http://www.mscui.net/PatientJourneyDemonstrator/

Hotfix for Visual Studio hang when opening Web project from a remote site
http://blogs.msdn.com/xmlteam/archive/2009/03/06/hotfix-for-visual-studio-hang-when-opening-web-project-from-a-remote-site.aspx

Creating JSON-enabled WCF services in .NET 3.5
http://www.pluralsight.com/community/blogs/fritz/archive/2008/01/31/50121.aspx

http://dotnetslackers.com/articles/ajax/JSON-EnabledWCFServicesInASPNET35.aspx


http://jeffbarnes.net/portal/blogs/jeff_barnes/archive/2007/11/19/how-to-ajax-enable-a-wcf-service.aspx

http://geekswithblogs.net/technetbytes/archive/2008/05/29/122496.aspx

http://msdn.microsoft.com/en-us/library/bb412167.aspx

http://www.codeproject.com/kb/ajax/aspnetchat.aspx



Unable to add data connection
http://usedotnet.blogspot.com/2008/10/visual-studio-2008-error.html

Stored procedures to implement paging for large tables or queries in SQL Server 2005 and SQL Server 2008
http://www.mssqltips.com/tip.asp?tip=1699

Using CSS and Styles with the Menu Control
http://msdn.microsoft.com/en-us/library/ms366731.aspx


Using Linq To SQL with ObjectDataSource Control
http://weblogs.asp.net/zeeshanhirani/archive/2008/05/05/using-linq-to-sql-with-objectdatasource-control.aspx

http://www.c-sharpcorner.com/UploadFile/scottlysle/GenericL2SinCS07212008041344AM/GenericL2SinCS.aspx



http://cgeers.wordpress.com/2008/12/06/aspnet-menu-sliding-doors-of-css/#download

http://cgeers.wordpress.com/download/



Output Caching Master Page in ASP.NET
http://dotnetperls.com/Content/Output-Caching-Master-Page.aspx

How To Call WebService
http://silverlight.net/forums/p/24005/86700.aspx#86700

http://weblogs.asp.net/nilotpal/archive/2008/09/19/hosting-a-service-on-iis.aspx


SharePoint URL:
http://pramodtech.blogspot.com/2007/05/moss-2007-faqs.html

Mobile URL:
http://cid-0779b8ef58de4561.skydrive.live.com/browse.aspx/Public


===========
http://aspnetinfo.googlepages.com/home

http://moredotnet.googlepages.com

1) C:\WINDOWS\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\ServiceModelReg.exe –i

2) iisreset

OR

1) aspnet_regiis –ua
2) aspnet_regiis –i
3) C:\WINDOWS\Microsoft.NET\Framework\v3.0\Windows Communication Foundation\ServiceModelReg.exe –i
4) iisreset

Using Page.ClientScript.RegisterClientScriptBlock
The RegisterClientScriptBlock method allows you to place a JavaScript function at the top of the
page. This means that the script is in place for the startup of the page in the browser.

C#




Using Page.ClientScript.RegisterStartupScript
The RegisterStartupScript method is not too much different from the RegisterClientScriptBlock
method. The big difference is that the RegisterStartupScript places the script at the bottom of the
ASP.NET page instead of at the top.

protected void Page_Load(object sender, EventArgs e)
{
string myScript = @"alert(document.forms[0][’TextBox1’].value);";
Page.ClientScript.RegisterStartupScript(this.GetType(),
"MyScript", myScript, true);
}

Using Page.ClientScript.RegisterClientScriptInclude
The final method is RegisterClientScriptInclude. Many developers place their JavaScript inside a
.js file, which is considered a best practice because it makes it very easy to make global JavaScript
changes to the application. You can register the script files on your ASP.NET pages using the Register-
ClientScriptInclude method

C#
string myScript = "myJavaScriptCode.js";
Page.ClientScript.RegisterClientScriptInclude("myKey", myScript);
This creates the following construction on the ASP.NET page:

Alert/Prevent Users From closing the browser

Here's a simple script that works on both IE and Mozilla and displays a confirmation box before closing the browser. You can use this script to detect if an activity is on and alert users about the same, before they close the browser.

Open a PopUp Window on the ASP.NET Button Click event and pass Parameters

A User asked me how to Open a PopUp window when the user clicks on an ASP.NET Button Server Control. He also wanted to pass parameters to the url. Here's how it is done:

C#


protected void Button1_Click(object sender, EventArgs e)


{


string queryString =


"http://localhost:39208/TreeView.aspx?param1="


+ TextBox1.Text.Trim();


string newWin =


"window.open('" + queryString + "');";


ClientScript.RegisterStartupScript


(this.GetType(), "pop", newWin, true);


}




VB.NET


Protected Sub Button1_Click(ByVal sender As Object, _


ByVal e As EventArgs)


Dim queryString As String = _


"http://localhost:39208/TreeView.aspx?param1=" & _


TextBox1.Text.Trim()


Dim newWin As String = _


"window.open('" & queryString & "');"


ClientScript.RegisterStartupScript(Me.GetType(), _


"pop", newWin, True)


End Sub

Export GridView to Excel

Users often post a requirement to export the data in an ASP.NET GridView to Excel. Here's a simple way to do so:

C#


protected void Button1_Click(object sender, EventArgs e)


{


Response.AddHeader("content-disposition",

"attachment;filename=FileName.xls");


Response.Charset = String.Empty;


Response.ContentType = "application/vnd.xls";


System.IO.StringWriter sw = new System.IO.StringWriter();


System.Web.UI.HtmlTextWriter hw = new HtmlTextWriter(sw);


GridView1.RenderControl(hw);


Response.Write(sw.ToString());


Response.End();


}




VB.NET


Protected Sub Button1_Click(ByVal sender As Object, _

ByVal e As EventArgs)


Response.AddHeader("content-disposition", _

"attachment;filename=FileName.xls")


Response.Charset = String.Empty


Response.ContentType = "application/vnd.xls"


Dim sw As System.IO.StringWriter = _

New System.IO.StringWriter()


Dim hw As System.Web.UI.HtmlTextWriter = _

New HtmlTextWriter(sw)


GridView1.RenderControl(hw)


Response.Write(sw.ToString())


Response.End()


End Sub




To read about some more tips and tricks about the GridView, check GridView Tips and Tricks using ASP.NET 2.0

Supress Postback on an ASP.NET ImageButton

If you are looking to suppress a postback on an imagebutton, then the following code should be helpful:

ASP.NET Image Button

Using MarkUp - Observe the onClientClick event



runat="server" OnClientClick="return false;" />

Using Code Behind:

C#


protected void Page_Load(object sender, EventArgs e)


{


btnShow.Attributes.Add("onclick", "return false;");


}




VB.NET


Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)


btnShow.Attributes.Add("onclick", "return false;")


End Sub

HTML Image Button

To prevent postback on an HTML Image button, use the following tag:



onclick="return false;" src="Images/Show.gif" />

Convert Domain Name to I.P Address

A user asked me on the forums if it was possible to convert a domain name to an I.P. Address. The answer is quiet simple. Just use the System.Net.Dns class

C#


using System.Net;


protected void Page_Load(object sender, EventArgs e)


{


foreach (IPAddress address in


Dns.GetHostAddresses("www.devcurry.com"))


{


Response.Write(address.ToString());


}


}




VB.NET


Imports System.Net


Protected Sub Page_Load(ByVal sender As Object, _


ByVal e As EventArgs)


For Each address As IPAddress In


Dns.GetHostAddresses("www.devcurry.com")


Response.Write(address.ToString())


Next address


End Sub

How to Create an ASP.NET AJAX ModalPopUp Extender Dynamically

You may need to create a ModalPopUpExtender dynamically. Here's some code on how to do so:

Add the following markup in your page:

Text="CreateModal" OnClick="Button1_Click" />




Style="display: none"

BackColor="Gray">

Dynamic ModalPopup!

Then in the code behind, add the following code. On clicking the Button, we have added code to create another button dynamically which contains functionality to show and hide a ModalPopUp

C#


protected void Button1_Click(object sender, EventArgs e)

{

Button btnNew = new Button();

btnNew.ID = "Button2";

btnNew.Text = "Click Me to Show PopUp";



AjaxControlToolkit.ModalPopupExtender modalPop =

new AjaxControlToolkit.ModalPopupExtender();

modalPop.ID = "popUp";

modalPop.PopupControlID = "ModalPanel";

modalPop.TargetControlID = "Button2";

modalPop.DropShadow = true;

modalPop.CancelControlID = "btnCancel";



this.Panel1.Controls.Add(modalPop);

this.Panel1.Controls.Add(btnNew);



}



VB.NET


Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)

Dim btnNew As New Button()

btnNew.ID = "Button2"

btnNew.Text = "Click Me to Show PopUp"



Dim modalPop As New AjaxControlToolkit.ModalPopupExtender()

modalPop.ID = "popUp"

modalPop.PopupControlID = "ModalPanel"

modalPop.TargetControlID = "Button2"

modalPop.DropShadow = True

modalPop.CancelControlID = "btnCancel"



Me.Panel1.Controls.Add(modalPop)

Me.Panel1.Controls.Add(btnNew)



End Sub

Ask For Confirmation Before Submitting Data in ASP.NET

Here's a simple way to ask the user for confirmation before submitting data:

C#

protected void Page_Load(object sender, EventArgs e)

{

string myScript = @"";

Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "MakeSure", myScript);

form1.Attributes.Add("onsubmit", "return askBeforeSubmit();");

}




VB.NET

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

Dim myScript As String = ""

Page.ClientScript.RegisterClientScriptBlock(Me.GetType(), "MakeSure", myScript)

form1.Attributes.Add("onsubmit", "return askBeforeSubmit();")



End Sub




You can also ask for confirmation without writing any code. Just use the OnClientClick event on the button as shown below:


OnClientClick="return confirm('Are you sure?');"/>

How to execute javascript onLoad only once in an ASP.NET page

If you are working on a ASP.NET Master/Content Page scenario and have declared a javascript onload, then the script gets executed every on every postback.

However if you would like to execute it only once during the first postback, then here's how to do so:
Copy this code in the of your MasterPage



The code determines if there is a postback in Javascript and then executes code based on the result. Hence the alert popup is shown only once.

You can several other tips related to calling JavaScript in Master/Content Pages over here:

Calling JavaScript from ASP.NET Master Page and Content Pages - Part I

Calling JavaScript from ASP.NET Master Page and Content Pages - Part II

Ask user before closing the browser - IE and Mozilla

If you would like to ask the user for confirmation before closing the browser, then here's how to do so. You can use this script on an ASP.NET page or a simple HTML page.

Add OnKeyUp to an ASP.NET TextBox

Here's a simple technique to add OnKeyUp to an ASP.NET Textbox. In the Page_Load add the following code:

C#


protected void Page_Load(object sender, EventArgs e)

{

TextBox1.Attributes.Add("onKeyUp", "CallScript(this)");

}





VB.NET


Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

TextBox1.Attributes.Add("onKeyUp", "CallScript(this)")

End Sub

How to do a Page PostBack With a Delay

Here's a simple way to delay a Page PostBack.

Add the following code in the Page_Load event:

C#


protected void Page_Load(object sender, EventArgs e)

{

TimeSpan ts = new TimeSpan(0, 0, 0, 5);

System.Threading.Thread.Sleep(ts);

}



VB.NET


Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

Dim ts As New TimeSpan(0, 0, 0, 5)

System.Threading.Thread.Sleep(ts)

End Sub




Note: Avoid using this approach too much in a Production environment.

How to apply CSS to a GridView Row based on a condition

Assuming you have a GridView with a 'Discontinued' column. You now want to apply a different css class for all the rows that are Discontinued, then here's how to do so.

C#


protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)

{

if (e.Row.RowType == DataControlRowType.DataRow)

{

DataRowView drv = e.Row.DataItem as DataRowView;

if (drv["Discontinued"].ToString() == "true")

e.Row.CssClass = "selected";

}

}



VB.NET


Protected Sub GridView1_RowDataBound(ByVal sender As Object, _

ByVal e As GridViewRowEventArgs)

If e.Row.RowType = DataControlRowType.DataRow Then

Dim drv As DataRowView = TryCast(e.Row.DataItem, DataRowView)

If drv("Discontinued").ToString() = "true" Then

e.Row.CssClass = "selected"

End If

End If

End Sub

How to refresh an ASP.NET GridView automatically at regular intervals

A common requirement is to refresh the GridView after regular intervals. ASP.NET contains the Timer control which comes in very handy to achieve such requirements. Here's how to do so:

Add the GridView and the Timer control inside an ASP.NET AJAX UpdatePanel as shown below :

<asp:UpdatePanel ID="UpdatePanel1" runat="server">

<ContentTemplate>

<asp:Timer ID="Timer1" runat="server" Interval="3600" ontick="Timer1_Tick">asp:Timer>

<asp:GridView ID="GridView2" runat="server" AutoGenerateColumns="False" DataKeyNames="CustomerID"

DataSourceID="SqlDataSource1" AllowPaging="True" AllowSorting="True">

<Columns>

<asp:BoundField DataField="CustomerID" HeaderText="CustomerID" ReadOnly="True" SortExpression="CustomerID" />

<asp:BoundField DataField="CompanyName" HeaderText="CompanyName" SortExpression="CompanyName" />

<asp:BoundField DataField="ContactName" HeaderText="ContactName" SortExpression="ContactName" />

<asp:BoundField DataField="Address" HeaderText="Address" SortExpression="Address" />

<asp:BoundField DataField="City" HeaderText="City" SortExpression="City" />

Columns>

asp:GridView>

ContentTemplate>

asp:UpdatePanel>

Then in the code behind, add the following code which refreshes the GridView after every minute

C#

protected void Timer1_Tick(object sender, EventArgs e)

{

GridView2.DataBind();

}

VB.NET

Protected Sub Timer1_Tick(ByVal sender As Object, ByVal e As EventArgs)

GridView2.DataBind()

End Sub

Opening a new window from code behind on Button Click in ASP.NET

If you are looking out for server side code to open a new window on Button Click, then here's how to do so.

Add the following script to the section of your page

<script language="javascript" type="text/javascript">

function openNewWin(url) {

var x = window.open(url, 'mynewwin', 'width=600,height=600,toolbar=1');

x.focus();

}

script>

Then add a Button Control in the following manner


<asp:Button ID="btnOpenPop" runat="server" Text="Open Pop"

onclick="btnOpenPop_Click" />

Finally add some code in the code behind file

C#


protected void btnOpenPop_Click(object sender, EventArgs e)

{

string url = "http://www.dotnetcurry.com";

ClientScript.RegisterStartupScript(this.GetType(), "OpenWin", "");

}



VB.NET


Protected Sub btnOpenPop_Click(ByVal sender As Object, ByVal e As EventArgs)

Dim url As String = "http://www.dotnetcurry.com"

ClientScript.RegisterStartupScript(Me.GetType(), "OpenWin", "")

End Sub

I have created my own Role Provider

Question :
==========

I have created my own Role Provider because I found the one that ASP.Net provides to be way too bulky in

terms of tables in the database. I found implementing a custom RoleProvider to be quite easy.

My only problem is that right now I cannot have multiple roles for a page. I saw somewhere that at the top of

your class you need to "anotate it" with some security code. This is what I have

[PrincipalPermission(SecurityAction.Demand, Role="Admin")]If I try to include multiple roles by using a comma

separated list I get errors. If i try to specify multiple role keys then I also get errors. Do i Need to

specify multiple PrinicipalPermissions by any chance?

I have very little experience with ASP.Net's role management. Can someone point me in the right direction or

at some good literature.

Answer:
=======
Hi, you can add the PrinicpalPermission attribute multiple times.

[PrincipalPermission(SecurityAction.Demand, Role="Admin")]
[PrincipalPermission(SecurityAction.Demand, Role="AnotherRole")]

Hiding a File using C# and VB.NET

The FileInfo class is very useful class that contains methods for the creation, copying, deletion, moving,

and opening of files. Here’s how to hide a file using C# and VB.NET

C#

class Program
{
static void Main(string[] args)
{
try
{
string filePath = @"D:\Network.txt";
FileInfo f = new FileInfo(filePath);
f.Attributes = FileAttributes.Hidden;
Console.WriteLine("File Hidden");
}
catch (Exception ex)
{
// handle ex
}
}
}

Accessing the ASP.NET Authentication, Profile and Role Service in Silverlight

http://tv.sys-con.com/node/581103

Accept dd/mm/yyyy date format in ASP.NET AJAX MaskedEditExtender

A simple way to use the dd/mm/yyyy date format in the ASP.NET AJAX MaskedEditExtender is to use a culturename in the extender that supports this format. Shown below is an example which accepts the date in dd/mm/yyyy format and also use a MaskedEditValidator for a date field. The CultureName used here is of Great Britain "en-GB"









CultureName="en-GB" TargetControlID="txtDate"

Mask="99/99/9999" MaskType="Date" AcceptNegative="None"/>


ControlExtender="MaskedEditExtender1"

EmptyValueMessage="Please enter Date" InvalidValueMessage="Invalid Date"

ControlToValidate="txtDate" ValidationGroup="DtVal" />

Adding OnClick event to an ASP.NET Label control

It's a strange requirement, but I bumped into it when helping out a user on the forums. Here's how to add an OnClick event to the ASP.NET Label Control

Now in the Code Behind, use the Control.Attributes.Add() to add the OnClick event to the Label Control

C#


protected void Page_Load(object sender, EventArgs e)

{

Label1.Attributes.Add("onClick", "CallMe();");

}



VB.NET




Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

Label1.Attributes.Add("onClick", "CallMe();")

End Sub

Display an Image for EmptyData in an ASP.NET GridView

The GridView’s EmptyDataText property allows you display a message when there are no results returned from the GridView control’s data source.

However if you want to display an image instead of text when no results are returned, then here's how to do so:





ImageUrl="~/images/NoDataFound.jpg"

AlternateText="No data found"

runat="server"/>







Shown above is an EmptyDataTemplate that can be used within the GridView. Inside the , we are using the image control to display an image when no records are returned

How do you programmatically determine if an ASP.NET application is running locally

A user recently popped up a question on the forums asking if it was possible to determine that his asp.net app is running on the local machine. Well there were suggestions to check for the local address 127.0.0.1 or check http://localhost.

How to do this the reliable way, a very simple solution is to use the 'isLocal' property of the Request class as shown below:

C#


protected void Page_Load(object sender, EventArgs e)

{

if (HttpContext.Current.Request.IsLocal)

{

Response.Write("App is local");

}

}



VB.NET


Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)

If HttpContext.Current.Request.IsLocal Then

Response.Write("App is local")

End If

End Sub

Change DateFormat In an ASP.NET GridView

While displaying dates in the GridView, a very common requirement is to display the date format in a user friendly manner. By default, the HTMLEncode property of a BoundField is set to True, which makes it difficult to format the date.

Note: HTMLEncode=True helps prevent cross-site scripting attacks.

In order to display the date in a user friendly date format, use the following method to turn off the HTMLEncode and use :



DataSourceID="SqlDataSource1" AllowPaging="True" AllowSorting="True">




HtmlEncode="false" HeaderText="SomeDate" />

...







If you do not want to do it this way, the other way is to use a Template Field as shown below



DataSourceID="SqlDataSource1" AllowPaging="True" AllowSorting="True">














...

Creating a Dynamic Hyperlink in ASP.NET using the Web.Config

A user recently asked me that she wanted to create a bunch of hyperlinks whose value comes from a web.config. However she was not able to create the Hyperlink successfully by reading the key pair values. Here's how to do so:










Now read this entry from the web.config using AppSettings



NavigateUrl="<%$ Appsettings:someurl %>" Text="Click Here">

Display the First and Last Day of Week In ASP.NET

Use the DateTime class to display the First Day and Last of the Week. Here's how

C#


DateTime dt = DateTime.Now;

DateTime wkStDt = DateTime.MinValue;

DateTime wkEndDt = DateTime.MinValue;

wkStDt = dt.AddDays(1 - Convert.ToDouble(dt.DayOfWeek));

wkEndDt = dt.AddDays(7 - Convert.ToDouble(dt.DayOfWeek));

Response.Write(wkStDt.ToString("MMMM-dd") + "
");

Response.Write(wkEndDt.ToString("MMMM-dd"));



VB.NET


Dim dt As DateTime = DateTime.Now

Dim wkStDt As DateTime = DateTime.MinValue

Dim wkEndDt As DateTime = DateTime.MinValue

wkStDt = dt.AddDays(1 - Convert.ToDouble(dt.DayOfWeek))

wkEndDt = dt.AddDays(7 - Convert.ToDouble(dt.DayOfWeek))

Response.Write(wkStDt.ToString("MMMM-dd") & "
")

Response.Write(wkEndDt.ToString("MMMM-dd"))

How to add Control dynamically in an ASP.NET AJAX application

Most of us know how to create controls dynamically in an ASP.NET application. However a lot of users get confused while creating controls dynamically in an ASP.NET AJAX application. This is as the there is an async postback involved. Here's a very common technique to create controls dynamically in an ASP.NET AJAX application using ViewState

C#


protected void Button1_Click(object sender, EventArgs e)

{

int cnt = 0;



if (ViewState["txtBoxes"] != null)

cnt = (int)ViewState["txtBoxes"];



cnt = cnt + 1;

ViewState["txtBoxes"] = cnt;





for (int i = 0; i < cnt; i++)

{

TextBox tb = new TextBox();

tb.Text = "";

tb.ID = "TextBox" + cnt;

UpdatePanel1.ContentTemplateContainer.Controls.Add(tb);

}

}



VB.NET


Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)

Dim cnt As Integer = 0



If ViewState("txtBoxes") IsNot Nothing Then

cnt = CInt(Fix(ViewState("txtBoxes")))

End If



cnt = cnt + 1

ViewState("txtBoxes") = cnt





For i As Integer = 0 To cnt - 1

Dim tb As New TextBox()

tb.Text = ""

tb.ID = "TextBox" & cnt

UpdatePanel1.ContentTemplateContainer.Controls.Add(tb)

Next i

End Sub

Display Message On MouseOver In an ASP.NET GridView

To display a message in an ASP.NET GridView on MouseOver, handle the RowDataBound event. As given in MSDN,

The RowDataBound event is raised when a data row (represented by a GridViewRow object) is bound to data in the GridView control. This enables you to provide an event-handling method that performs a custom routine, such as modifying the values of the data bound to the row, whenever this event occurs.





SelectCommand="SELECT [CustomerID], [CompanyName], [ContactName], [Address], [City] FROM [Customers]">






DataSourceID="SqlDataSource1" AllowPaging="True" AllowSorting="True"

OnRowDataBound="GridView1_RowDataBound">



















C#


protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)

{

if ( e.Row.RowType == DataControlRowType.DataRow )

{

e.Row.Attributes.Add("onmouseover", "alert('Display some message');");

}

}



VB.NET


Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)

If e.Row.RowType = DataControlRowType.DataRow Then

e.Row.Attributes.Add("onmouseover", "alert('Display some message');")

End If

End Sub

Hiding a Column in an ASP.NET GridView

Two of the many ways you can hide a column in an ASP.NET GridView are as follows:

1. Set the GridView column’s 'Visibility' property to 'False'. However in this case, GridView will not bind the data to the GridView. So if you want to use that hidden column (like a Master-Detail scenario), you won't be able to do it.

You can also hide the column programmatically in the RowDataBound event


protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)

{

e.Row.Cells[0].Visible = false;

}



VB.NET


Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)

e.Row.Cells(0).Visible = False

End Sub



2. Use the OnRowCreated event which gets called after the data is bound

C#


protected void GridView1_OnRowCreated(object sender, GridViewRowEventArgs e)

{

e.Row.Cells[0].Visible = false;

}



VB.NET


protected void GridView1_OnRowCreated(object sender, GridViewRowEventArgs e)

{

e.Row.Cells[0].Visible = false;

}



Using this way, you can use a hidden column's data even if it is hidden.

Fetching all controls on a page ordered by their ID

Here's a simple to way to fetch all the controls on an ASP.NET page ordered by their ID's

C#



protected void Button1_Click(object sender, EventArgs e)

{

var ctrl = from ctr in this.Controls.Cast().OrderBy(c => c.ID)

select ctr;

}



VB.NET


Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs)

Dim ctrl = _

From ctr In Me.Controls.Cast(Of Control)().OrderBy(Function(c) c.ID) _

Select ctr

End Sub

How to Prevent Word Wrap in an ASP.NET GridView

Recently I came across an interesting answer by Jason, where he suggests how to stop word wrap in an ASP.NET GridView. I thought of sharing this trick with the viewers facing similar issues:

The trick is to use





Check this sample:





HorizontalAlign="Left"
Wrap="True" />

runat="server"
Text='<%# Bind("SomeLongText") %>'>

I am sure there are many developers who had this problem in the past without a decent solution. Let me know if it worked for you!

How to find all the checked checkboxes in an asp.net gridview

I have seen this question a gazillion times on the forums – Finding checked checkboxes in an ASP.NET GridView. Here’s how to do so. The CheckBox in our example is in a TemplateField as shown below:

<asp:TemplateField>  

   <ItemTemplate >     

      <asp:CheckBox id="CheckBox1" runat="server" /> 

    ItemTemplate>

asp:TemplateField>

In order to find the checked checkboxes on a button click, use this simple code

C#

    protected void Button1_Click(object sender, EventArgs e)

   {   

       foreach (GridViewRow gvr in GridView1.Rows)

       {

           CheckBox chkBox = (CheckBox)gvr.FindControl("CheckBox1");

           if (chkBox != null && chkBox.Checked)

           {



           }

       }

   }

VB.NET

Protected Sub Button1_Click(ByVal sender As Object, _

ByVal e As EventArgs)

   For Each gvr As GridViewRow In GridView1.Rows

       Dim chkBox As CheckBox = _

          CType(gvr.FindControl("CheckBox1"), CheckBox)

       If chkBox IsNot Nothing AndAlso chkBox.Checked Then

       ' Do Something

       End If

   Next gvr

End Sub

3 quick things to check if your ASP.NET session ends before timeout

Session ending before timeout is an issue faced by many developers who use IIS 6. I have found that in most cases, this is caused when you set the recycling of worker processes using IIS manager.

Check this cool post to understand this better.

Here are 3 quick suggestions to troubleshoot this issue (assuming that you are using In-process mode - ASP.NET session state):

1. Check and see if you have configured recycling of worker processes

2. If you are maintaining cookie enabled sessions, check if the cookie is not getting deleted/modified at the client end.

3. Check to see if IIS/Application Pool is not getting restarted at regular intervals. Your application pool will restart if your global.asax or the web.config/ machine.config changes

Cause a PostBack on KeyPress from the asp.net dropdownlist

I recently bumped into a solution given by Vince Xu where he suggested a technique of causing a postback from a dropdownlist on any keypress. If you desire, you can easily filter the key code and cause postback on specific keypress. This technique can be useful when you plan to Implementing KeyBoard Shortcuts in ASP.NET applications

Here’s how to cause a postback from DropDownList on keypress

C#

protected void Page_Load(object sender, EventArgs e)
{
if (Request.Params["__EVENTTARGET"] != null)
{
string evnt = Request.Params["__EVENTTARGET"].ToString();
string args = Request.Params["__EVENTARGUMENT"].ToString();
if (evnt == "DropDownList1" && args == "onkeypress")
{
// write some code to execute on postback
}
}

DropDownList1.Attributes.Add("onkeypress",
Page.GetPostBackEventReference(DropDownList1,"onkeypress"));
}




VB.NET



Protected Sub Page_Load(ByVal sender As Object, _
ByVal e As EventArgs)
If Request.Params("__EVENTTARGET") IsNot Nothing Then
Dim evnt As String = _
Request.Params("__EVENTTARGET").ToString()
Dim args As String = _
Request.Params("__EVENTARGUMENT").ToString()
If evnt = "DropDownList1" _
AndAlso args = "onkeypress" Then
' write some code to execute on postback
End If
End If

DropDownList1.Attributes.Add("onkeypress",_
Page.GetPostBackEventReference(DropDownList1, "onkeypress"))
End Sub

Adding a ToolTip to an ASP.NET Hyperlink Control in a GridView

I recently came across a cool solution proposed by Jose to add a tooltip to an ASP.NET Hyperlink control kept inside a GridView. The solution is to create a template field and add a Hyperlink control to it as shown below:

<asp:TemplateField HeaderText="SomeLink">

<ItemTemplate>

     <asp:HyperLink ID="HyperLink1" runat="server"

     NavigateUrl='<%# Eval("SomeLink") %>' Text='<%# Eval("SomeLink") %>'

     ToolTip='<%# Eval("SomeText") %>'>       

     asp:HyperLink>   

ItemTemplate>

asp:TemplateField>

How to Reduce the Margin/Padding around a CheckBox

I was creating a HTML form recently which involved a lot of checkboxes. The client needed the space between the checkbox and the text to be reduced. An obvious choice was to reduce the Margin and Padding around the checkboxes, however this did not work around different browsers. I finally emulated the effect using the width of the checkbox. Here’s how:

One

Two

Three

Four

Output

image

Check out the first two checkboxes which have the default width, margin and padding. Now check out the last two checkboxes which have a reduced width, margin and padding.

This tip should save time for those who have been trying to do the same using the margin and padding properties. The trick is to also set the width property.

How to Debug Client-Side Script In Internet Explorer

If you have got a lot of JavaScript code in your ASP.NET pages, chances are you have to debug it at some point of time to fix a bug or test the output. In IE, you need to explicitly enable debugging support inside the browser. Follow these steps to do so:

Open IE > Tools > Internet Options

Click Advanced Tab > Under the ‘Browsing’ section, clear the checkbox against ‘ Disable script debugging (Internet Explorer)’.

image

That’s it. Now put a breakpoint in your JavaScript code and run the application in Visual Studio.

There are other tools like Microsoft Script Editor too which can be used.

Other browsers like Firefox has tools like FireBug, which is a great tool to debug Client-Side Script.

How To: Use Forms Authentication with Active Directory in ASP.NET 2.0

http://msdn.microsoft.com/en-us/library/ms998360.aspx

ASP.NET Session Expiration Redirect

Most of the applications I work with require some form of authentication and a timed expiration of the authentication ticket and session object. When the expiration takes place it can wreak havoc on your application code if you are relying on the Session object or have authentication code in place to ensure that the user is authenticated before you serve up any data for them.

Unfortunately ASP.NET doesn't provide a nice out of the box solution for handling the session timeout gracefully. Everything expires behind the scenes and your user is left unaware of what has happened. Additional problems can arise if the user abandoned their browser in a state that you didn't code for, which can result in errors or exceptions taking place.

With this in mind I like to put a Session Expired page in place in my applications and pro-actively send the user there when their session ends. This accomplishes a few different things:

1) Provides a nice user experience for your users
2) Prevents your application from being left in an unknown state when the session / auth ticket expires
3) Prevents application errors and exceptions from occurring when a user tries to perform an action on a page after their session / auth ticket has expired
Nested MasterPage(s) For All Authenticated Pages

You need to implement a MasterPage (or a Page base class) for all of your authenticated pages so you can inject a bit of javascript to handle the redirect on session timeout.
Get Your Web.config Settings Straight

Make sure that your auth ticket timeout and session timeout match.












protection="All"

path="/"

requireSSL="false"

timeout="45"

name=".ASPXAUTH"

slidingExpiration="true"

defaultUrl="Login.aspx"

cookieless="UseDeviceProfile"

enableCrossAppRedirects="false" />





Create Your Session Expiration Page


Create a page for your users to be taken to when their session expires. I created SessionExpired.aspx with the following message:

Session Expired

Your session has expired due to inactivity.







Click here to login again

Ensure the Authentication ticket is signed out in your code behind:


FormsAuthentication.SignOut();



Add The Session Expiration Javascript To Your Page_Load


In the Page_Load method of your MasterPage (or base page class) add the following code:


// Handle the session timeout

string sessionExpiredUrl = Request.Url.GetLeftPart(UriPartial.Authority) + "/SessionExpired.aspx";

StringBuilder script = new StringBuilder();

script.Append("function expireSession(){ \n");

script.Append(string.Format(" window.location = '{0}';\n", sessionExpiredUrl));

script.Append("} \n");

script.Append(string.Format("setTimeout('expireSession()', {0}); \n", this.Session.Timeout * 60000)); // Convert minutes to milliseconds

this.Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "expirescript", script.ToString(), true);



That's It


The session timeout script should be injected into each of your authenticated pages now. The client's browser will begin the countdown after each page has loaded or each PostBack has occurred. Once the countdown is reached the browser will redirect to your SessionExpired page.


Reference:

http://msmvps.com/blogs/shahed/archive/2007/09/05/redirect-to-login-page-on-session-expiration-asp-net.aspx


Aaron Schnieder

http://www.churchofficeonline.com

[PATCH] Fix for Membership.{Encrypt, Decrypt}Password

http://lists.ximian.com/pipermail/mono-devel-list/2006-November/021467.html

WCSF Application Architecture 1: Introduction

http://blogs.msdn.com/simonince/archive/2008/06/05/wcsf-application-architecture-1-introduction.aspx

Caching LinqToSql results with SqlCacheDependency

Caching Linq results using SqlCacheDependency
In early 2008 I needed to cache the results from LinqToSql-queries. I like the SqlCacheDependency (especially in SQL 2K5 Server).
I also like the new extension methods posibillity... So this is what I came up with.

SqlCacheDependency
With SqlServer 2005 SqlCacheDependency became very useful. In Sql 2000 the dependency could only be created on full tables (not rows). The Cache was destroyed as a table being cached changed even if your query did not affect the row changed, but Sql 2005 can handle SqlCacheDependency on row-level... Hence SqlCacheDependency is destroyed only if a row that my query affects is being changed.

The thing you do to use SqlCacheDependency is to create a SqlCommand that contains the Sql-query you want to cache the result of.
Then you create a SqlCacheDependency with the SqlCommand as a parameter.

LinqToSql
It´s hard not to love LinqToSql... Sure, I know some DBA´s that do not love the thought of foreign code executing queries in there databases (if we ignore the option to use stored procedures with LinqToSql). I personally think that it´s ok to only use permissions in BLL on method level like:
PrincipalPermission(System.Security.Permissions.SecurityAction.Demand,Role"ADMIN",Authenticatedtrue)

The simplicity of development and the oppurtunity to quick changes in DAL and database makes it hard to resist LinqToSql :)

SqlCacheDependency with LinqToSql
Why cache LinqQueries?
Everytime you iterate over a LinqToSql-query it will execute...
Like -> foreach(MyObj o in MyLinqQuery) will execute the query against the SqlServer. One solution I´ve seen people using is: List = MyLiqToSqlQuery.ToList(); and then use cache on the result. This will ofcourse work, but you´ll not know if anything changes in the database unless you use SqlCacheDependency.

The challenge of LinqToSql & SqlCacheDependency is to extract the SqlQuery to be able to store it in a SqlCommand and then use the SqlCommand in the SqlCacheDependency. You will also have to provide functionality for parameters that the LinqQuery may hold... I created a generic ExtensionMethod for IQueryable to solve my problem.... one method to cache all LinqQueries

The code should be explained enough by the comments I think.

public static class Cache
{
///

/// Caches Linq query´s that is created for LinqToSql.
/// Limitations are the same as SqlCacheDependency
///

///
/// The linq query
/// Your LinqToSql DataContext
/// The unique Id for the cache
///
public static List LinqCache(this System.Linq.IQueryable q, System.Data.Linq.DataContext dc, string CacheId)
{
try
{
List objCache = (List)System.Web.HttpRuntime.Cache.Get(CacheId);

if (objCache == null)
{
/////////No cache... implement new SqlCacheDependeny//////////
//1. Get connstring from DataContext
string connStr = dc.Connection.ConnectionString;
//2. Get SqlCommand from DataContext and the LinqQuery
string sqlCmd = dc.GetCommand(q).CommandText;
//3. Create Conn to use in SqlCacheDependency
using (System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection(connStr))
{
conn.Open();
//4. Create Command to use in SqlCacheDependency
using (System.Data.SqlClient.SqlCommand cmd = new System.Data.SqlClient.SqlCommand(sqlCmd, conn))
{
//5.0 Add all parameters provided by the Linq Query
foreach (System.Data.Common.DbParameter dbp in dc.GetCommand(q).Parameters)
{
cmd.Parameters.Add(new System.Data.SqlClient.SqlParameter(dbp.ParameterName, dbp.Value));
}
//5.1 Enable DB for Notifications... Only needed once per DB...
System.Web.Caching.SqlCacheDependencyAdmin.EnableNotifications(connStr);
//5.2 Get ElementType for the query
string NotificationTable = q.ElementType.Name;
//5.3 Enable the elementtype for notification (if not done!)
if (!System.Web.Caching.SqlCacheDependencyAdmin.GetTablesEnabledForNotifications(connStr).Contains(NotificationTable))
System.Web.Caching.SqlCacheDependencyAdmin.EnableTableForNotifications(connStr, NotificationTable);
//6. Create SqlCacheDependency
System.Web.Caching.SqlCacheDependency sqldep = new System.Web.Caching.SqlCacheDependency(cmd);
// - removed 090506 - 7. Refresh the LinqQuery from DB so that we will not use the current Linq cache
// - removed 090506 - dc.Refresh(System.Data.Linq.RefreshMode.OverwriteCurrentValues, q);
//8. Execute SqlCacheDepency query...
cmd.ExecuteNonQuery();
//9. Execute LINQ-query to have something to cache...
objCache = q.ToList();
//10. Cache the result but use the already created objectCache. Or else the Linq-query will be executed once more...
System.Web.HttpRuntime.Cache.Insert(CacheId, objCache, sqldep);
}
}
}
//Return the created (or cached) List
return objCache;
}
catch (Exception ex)
{
throw ex;
}
}
}


IMPORTANT
You need to call SqlDependency.Start for example in global.asax

//In Application Start Event
System.Data.SqlClient.SqlDependency.Start("DataContextConnectionString");
//In Application End Event
System.Data.SqlClient.SqlDependency.Stop("DataContextConnectionString");


HowTo: Call the Extension Method
So now yo can get call LinqCache on any Linq.IQueryable...

How to Open a Page In Full Screen Mode using JavaScript

One of my team members had a requirement of opening up a page in Full Screen mode. He wanted that when a link on the page is clicked, the same page should be opened in Full Screen Mode. If you too have a similar requirement, then here’s how to do so:

DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"

"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">



<html xmlns="http://www.w3.org/1999/xhtml">

<head>

   <title>Open Page FullScreentitle>

   <script type="text/javascript"> 

   function   FullScreenMode(){

       var win = window.open("", "full", "dependent=yes, fullscreen=yes");

       win.location = window.location.href;

       window.opener = null;

   } 

 

   script>

 

head>

<body>

   <input id="Button1" type="button" value="Full Screen"

   onclick="FullScreenMode()"/>

body>

html>

If you want the parent window to close when the new window opens in full screen mode, just add window.close(); as the last line in the JavaScript code.

Import Excel Data Into An ASP.NET GridView using OLEDB

I have seen a lot of users asking how to import data from an excel sheet into an ASP.NET GridView.

I will show two ways to do so - Using OLEDB and Using Microsoft.Office.Interop.Excel

In this post, we will see how to import data using OLEDB

C#

using System.Data.OleDb;
using System.Data;

public partial class UploadD : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
   string cnstr = "Provider=Microsoft.Jet.Oledb.4.0;Data Source=C:\a.xls;"
   + "Extended Properties=Excel 8.0";
   OleDbConnection oledbConn = new OleDbConnection(cnstr);
   string strSQL = "SELECT * FROM [Sheet$]";

   OleDbCommand cmd = new OleDbCommand(strSQL, oledbConn);
   DataSet ds = new DataSet();
   OleDbDataAdapter da = new OleDbDataAdapter(cmd);
   da.Fill(ds);
   GridView1.DataSource = ds;
   GridView1.DataBind();
}
}

VB.NET

Imports System.Data.OleDb
Imports System.Data

Partial Public Class UploadD
   Inherits System.Web.UI.Page
   Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
   Dim cnstr As String = "Provider=Microsoft.Jet.Oledb.4.0;" &_
   "Data Source=C:\a.xls; Extended Properties=Excel 8.0"
       Dim oledbConn As New OleDbConnection(cnstr)
       Dim strSQL As String = "SELECT * FROM [Sheet$]"

       Dim cmd As New OleDbCommand(strSQL, oledbConn)
       Dim ds As New DataSet()
       Dim da As New OleDbDataAdapter(cmd)
       da.Fill(ds)
       GridView1.DataSource = ds
       GridView1.DataBind()
   End Sub
End Class

In the next article, we will see how to import Excel Data Into an ASP.NET GridView using Microsoft.Office.Interop.Excel

Import Excel Data Into an ASP.NET GridView using Microsoft.Office.Interop.Excel

In my previous article, we saw how to import Excel Data into an ASP.NET GridView using OLEDB. In this next article, we will see how to import Excel Data Into an ASP.NET GridView using Microsoft.Office.Interop.Excel. This untested code was written by Vince Xu -MSFT and I thought of sharing it with you.

C#

using Microsoft.Office.Interop.Excel;
using System.Text;
using System.Reflection;

public partial class ImportDD : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
   DataSet ds = GetExcel("c:\\aa.xls");
   GridView1.DataSource = ds;
   GridView1.DataBind();
}

public DataSet GetExcel(string fileName)
{
Application oXL;
Workbook oWB;
Worksheet oSheet;
Range oRng;
try
{
   //  creat a Application object
   oXL = new ApplicationClass();
   //   get   WorkBook  object
   oWB = oXL.Workbooks.Open(fileName, Missing.Value, Missing.Value,
           Missing.Value, Missing.Value, Missing.Value,
           Missing.Value, Missing.Value, Missing.Value,
           Missing.Value, Missing.Value, Missing.Value, Missing.Value,
           Missing.Value, Missing.Value);

   //   get   WorkSheet object
   oSheet = (Microsoft.Office.Interop.Excel.Worksheet)oWB.Sheets[1];
   System.Data.DataTable dt = new System.Data.DataTable("dtExcel");
   DataSet ds = new DataSet();
   ds.Tables.Add(dt);
   DataRow dr;

   StringBuilder sb = new StringBuilder();
   int jValue = oSheet.UsedRange.Cells.Columns.Count;
   int iValue = oSheet.UsedRange.Cells.Rows.Count;
   //  get data columns
   for (int j = 1; j <= jValue; j++)
   {
       dt.Columns.Add("column" + j, System.Type.GetType("System.String"));
   }

   //  get data in cell
   for (int i = 1; i <= iValue; i++)
   {
       dr = ds.Tables["dtExcel"].NewRow();
       for (int j = 1; j <= jValue; j++)
       {
           oRng = (Microsoft.Office.Interop.Excel.Range)oSheet.Cells[i, j];
           string strValue = oRng.Text.ToString();
           dr["column" + j] = strValue;
       }
       ds.Tables["dtExcel"].Rows.Add(dr);
   }
   return ds;
}
catch (Exception ex)
{
   return null;
}
finally
{
   Dispose();
}
}

}

VB.NET

Imports Microsoft.Office.Interop.Excel
Imports System.Text
Imports System.Reflection

Partial Public Class ImportDD
   Inherits System.Web.UI.Page
   Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
       Dim ds As DataSet = GetExcel("c:\aa.xls")
       GridView1.DataSource = ds
       GridView1.DataBind()
   End Sub

   Public Function GetExcel(ByVal fileName As String) As DataSet
       Dim oXL As Application
       Dim oWB As Workbook
       Dim oSheet As Worksheet
       Dim oRng As Range
       Try
           '  creat a Application object
           oXL = New ApplicationClass()
           '   get   WorkBook  object
oWB = oXL.Workbooks.Open(fileName, Missing.Value, Missing.Value,_
Missing.Value, Missing.Value,Missing.Value, Missing.Value, Missing.Value, _
Missing.Value, Missing.Value,Missing.Value, Missing.Value, Missing.Value, _
Missing.Value, Missing.Value)

           '   get   WorkSheet object
           oSheet = CType(oWB.Sheets(1),  _
           Microsoft.Office.Interop.Excel.Worksheet)
           Dim dt As New System.Data.DataTable("dtExcel")
           Dim ds As New DataSet()
           ds.Tables.Add(dt)
           Dim dr As DataRow

           Dim sb As New StringBuilder()
           Dim jValue As Integer = oSheet.UsedRange.Cells.Columns.Count
           Dim iValue As Integer = oSheet.UsedRange.Cells.Rows.Count
           '  get data columns
           For j As Integer = 1 To jValue
               dt.Columns.Add("column" & j, _
                              System.Type.GetType("System.String"))
           Next j

           '  get data in cell
           For i As Integer = 1 To iValue
               dr = ds.Tables("dtExcel").NewRow()
               For j As Integer = 1 To jValue
                   oRng = CType(oSheet.Cells(i, j),  _
                   Microsoft.Office.Interop.Excel.Range)
                   Dim strValue As String = oRng.Text.ToString()
                   dr("column" & j) = strValue
               Next j
               ds.Tables("dtExcel").Rows.Add(dr)
           Next i
           Return ds
       Catch ex As Exception
           Return Nothing
       Finally
           Dispose()
       End Try
   End Function

End Class