I want to Disable Button in asp.net

Dear All,

I create a CashBook in asp, Now it finish. Now I want to add a Confirm button in that page.
Some user Click that Confirm Button his username,date & time and status going to new sql table.
I do that thing. Bt I want to in that day if some user click this button at once want to disable that button in that button clicking user.
How I do that. Please help me.

Thank You!!!!

Rathnayake