HOW TO control ASP.NET's Adaptive Rendering behavior

ASP.NET server controls detect browser type automatically & render differently in modern non-IE browsers like Opera & Firefox. Sometimes this may be undesirable. For instance, a textbox server control with the property AutoCompleteType="Disabled" like so:

<asp:TextBox id="txtSecret" runat="server" AutoCompleteType="Disabled" >

</asp:TextBox>

is rendered as this in IE 6 -

<input name="txtSecret" type="text" autocomplete="off" id="txtSecret" />

whereas it will adaptively render without the autocomplete attribute in Firefox 2.0 like this -

<input name="txtSecret" type="text" id="txtSecret" />

Although the autocomplete attribute is a non-standard HTML property it is supported in Firefox. So how do we make this attribute show up in Firefox?

By setting the @ Page directive's ClientTarget property to "uplevel", we can force the page to render in Firefox (or any other non-IE browser) as it does in IE 6.

<%@ Page Language="C#" ClientTarget="uplevel" %>

You may have to verify that your other tags also render as desired in non-IE browsers.

Related reading:
ASP.NET Web Server Controls and Browser Capabilities
Architectural Overview of Adaptive Control Behavior
Dissecting Adaptive Rendering
A Look at ASP.NET's Adaptive Rendering