Mega Code Archive
Varying the Output Cache by a Custom Function
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You create the custom function in the Global.asax file by overriding the GetVaryByCustomString() method.
File: Global.asax
<%@ Application Language="C#" %>
<script runat="server">
public override string GetVaryByCustomString(HttpContext context, string custom)
{
if (String.Compare(custom, "css") == 0)
{
return Request.Browser.SupportsCss.ToString();
}
return base.GetVaryByCustomString(context, custom);
}
</script>
File: Default.aspx
<%@ Page Language="C#" %>
<%@ OutputCache Duration="3600" VaryByParam="none" VaryByCustom="css" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
void Page_Load()
{
if (Request.Browser.SupportsCss)
pnlCss.Visible = true;
else
pnlNotCss.Visible = true;
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
<title>Vary By Custom</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:Panel
id="pnlCss"
Visible="false"
Runat="server">
<span style="font-weight:bold">Hello!</span>
</asp:Panel>
<asp:Panel
id="pnlNotCss"
Visible="false"
Runat="server">
<b>Hello!</b>
</asp:Panel>
</div>
</form>
</body>
</html>
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