How to prevent duplicates when click on button?

Hi 2 all,

I have designed one page in asp.net,in that i keep ten controls(ex:textboxes,dropdowns etc)

my requirement is ,i want to save that controls data in sqlserver.
when i click on save button ,i will takes some time to save,in span of time   i will click once again on button ,i will saves same data again.

how to prevent dis duplicates.



Thanks inadvance