Question

When don’t you need to use runat="server" in ASP.NET?

EDIT: Thanks for all the answers, but I was really thinking of runat="server" inside an <asp: tag.

Answer 1

Use the runat=server attribute when you’re using ASP.NET controls, and/or you require programmatic access to those controls in your code-behind.

HTML controls don’t require this attribute. It’s useful if you have any HTML element like <span> <div>, or <table> when you want the ability to access them in code-behind.

<asp:Label runat="server" id="foo" />
<div runat="server" id="bar />
...
foo.Text = "Hello Label";
foo.Attributes["class"] = "baz";