Passing value from parent form to .NET control via javascript. Gridview Selectparameter from window.opener

I have two asp.net forms.

The first form opens a popup window to the second using onclick javascript as follows:

onclientclick="javascript:PS=window.open('https://site/PS.aspx','PS','width=800,height=600,scrollbars=1');PS.focus()"

the second form has a .net gridview with a SelectParameter.

 <Select开发者_开发问答Parameters>
 <asp:ControlParameter ControlID="???" Name="FirstName" DefaultValue="="  PropertyName="Text" Type="String" />
 </SelectParameters>
 </asp:SqlDataSource>

How can I set the value of the parameter to the value of control on the parent form? I don't want to use a session variable or a querystring if possible.

Thanks.

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You should be able to pull a value from the parent window like this:

On the parent form, add a hidden field and create a function like this to access it's value:

getParameterValue = function(){
    return document.getElementById("<%=HiddenCtrl.UniqueID%>").value;    
}

Add a hidden field in the child window too, and set the value like this:

document.getElementById("<%=ChildHiddenCtrl.UniqueID%>").value = window.opener.getParameterValue();

And then for your control parameter, use ChildHiddenCtrl:

<asp:ControlParameter ControlID="ChildHiddenCtrl" ... >