Does ASP.NET Web Forms prevent a double click submission?
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I'm working on an ASP.NET 4.0 Web Forms project, after a break of about 5 years, and I'm confused about the submit behaviour.

In the click event of a button, I sleep the thread so that I can click the submit button multiple times.

From what I can tell, ASP.NET is preventing the click event being called more than once. Is this true?

BTW: I've turned off javascript for this test.
