how to disable double click for submit button?

The other solution is,

btnSubmit.Attributes.Add("onclick", "this.disabled=true;" + GetPostBackEventReference(btnSubmit).ToString());

for this, you have to set UseSubmitBehaviour="false"

hi girish,

i tried it but it's not working.

Hi Hardik, 
         You can set "Enable" property of button to "false" once it is click.
And later after you have done with your entries reset the form and then set "Enable" property of button to "true".

Hope this helps you... :)