Setting the value of server side variable in javascript and wants to use that server side variable on page load.


I am trying to set the value of a server side variable in javascript and wants to use that variable on page load. 

Here is my sample code.


private string testVal = null;


private void registerScript(){

if (!this.Page.ClientScript.IsClientScriptBlockRegistered("RequestHeaderValidation"))


StringBuilder sb = new StringBuilder("" + Environment.NewLine);

sb.Append(" var version = '2.0'; " + Environment.NewLine);

sb.Append(" var isInstalled = Silverlight.isInstalled(version);" + Environment.NewLine);

sb.Append(" if (isInstalled)" + Environment.NewLine);

sb.Append(" {" + Environment.NewLine);

sb.Append(" '" + testVal + "' = 'Y'; " + Environment.NewLine); sb.Append(" }" + Environment.NewLine);

//sb.Append(" " + this.ClientScript.GetPostBackEventReference(this, string.Empty) + Environment.NewLine);

this.Page.ClientScript.RegisterStartupScript(this.GetType(), "RequestHeaderValidation", sb.ToString(), true);




protected override void OnInit(EventArgs e)






protected override void OnLoad(EventArgs e)


// Want to use the value of the variable (testval) here


// It should return me 'Y'



testVal is a page level variable. Setting the value of the testval in register script and wants to use that value in pageload.

I am getting null value. How can I get the value of that variable that is being set on registerscript method.

Please help.



8/21/2008 6:48:43 PM 24353 articles. 1 followers. Follow

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Looks like the same question answered here:



8/21/2008 6:57:26 PM


8/21/2008 9:12:41 PM

No problem. Glad I could help. BTW, that is about the 5th request this week for that same problem.



8/22/2008 11:28:06 AM

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