hi,

you have mentioned that the client script registration shud happen in "not PostBack" block which means in the Page_Load event. Is the following snippet is acceptable in the Page_Load event:

if(!IsPostBack)
{
string strRef = Page.ClientScript(/* receiving function and args */);
string strCallBackScr = "function A1(arg,context){" + strRef + " }";
Page.ClientScript.RegisterScriptBlock(this.GetType(), "CallServer", strCallBackScr, true);
}