prevent form from being submitted over and over again?

i have created a forum site for our local community but it turns out that it is possible for people to post a message many times over by clicking back and then re submitting again which i need to prevent.

if anyone has any ideas how i can do this plz let me know as i need to get it back up and running soon as it was a very popular part of our site and do not want to lose the members because of this isue i have now found.

thanks in advance for your help.


oh and Merry Xmas...

One method would be to have the form submit the time using the now() and the receiving script can check to see if a certain amount of time had passed since the submission. Details would be up to you to determine.

yeah just set a limit elsewhere as to how often they can post into the database.

If the DB is not very large, then you can call a function to check for some fields to see if there is an entry posted in the same day with same contents by the same user. If not, just insert else do nothing.