Hi lak,
Based on my understanding of your question:You want to start Ayncpostback immediately after search results page loaded.
If I have misunderstood ,please let me know.
Based on my understanding,please try the following code to resolve your issue:
<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
protected void Button1_Click(object sender, EventArgs e)
{
System.Threading.Thread.Sleep(3000);
TextBox1.Text = DateTime.Now.ToString();
}
</script>
<script type="text/javascript">
function delayLoad()
{
document.getElementById("<%= Button1.ClientID %>").click();
document.getElementById("<%= UpdateProgress1.ClientID %>").style.display = "block";
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>Untitled Page</title>
</head>
<body onload="javascript: delayLoad()">
<form id="form1" runat="server">
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<div visible="true"><asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" /></div>
</ContentTemplate>
</asp:UpdatePanel>
<asp:UpdateProgress ID="UpdateProgress1" runat="server" AssociatedUpdatePanelID="UpdatePanel1">
<ProgressTemplate>
Waiting..............
</ProgressTemplate>
</asp:UpdateProgress>
</div>
</form>
</body>
</html>
More informatin,see:Delaying Content Load using Timer and UpdatePanel & Controlling visibility of contents of collapsiblepanel & Start callback immediately after page loaded
Please tell me the result of this code.
Good luck.