I am using a hidden input type in my web form. But when I try to access
that variable in code behind module, it seems the module doesnt know about
the variable at all.

The code is like this

In WebForm:
<input type="hidden" id="username">
I am setting a value here on "Onclick" event of a HTML button and then submitting
it to the server.

In CodeModule(C#):
Label1.Text = username.Text

This gives an error. Is it wrong to access HTML control in code behind module???
Could any one please help me!!!