But User can press the back button to submit more time.<BR><BR>P.S <BR>supposed that after one important form submitted the contents of the form will be sent to database,data in the database don't permitted change through user submit the form more time.
Use a cookie.<BR><BR>Check that cookie each time the form is pulled up.<BR>Let's say the cookie says - done<BR>then the user won't see a submit button.<BR>if it's says - notdone<BR>then the user sees the submit button.<BR>or<BR>record the ip each time for is submitted (submit it along using<BR>a hidden field into the db)<BR>then check that each time the form is pulled up.<BR><BR>Boom-bastic-shangralah hiza!
If you just use a condition for your database update based on the Cookie.<BR><BR>So, <BR><BR>If cookie is not present then <BR> add info to database<BR>End If<BR><BR>That way after the first time they add the info you also add the cookie. so if they press "back" it will read the cookie and skip the database update.
thank you everyone here. <BR>i will consider your suggestions .<BR><BR>but i am a beginner,i hope to get the details about the operation,wellcome email to me <BR>email@example.com <BR><BR>thank you again!