Prevent Double Entry in HTML/XHTML Posted June 21 · Report reply Sorry. I guess I wasn't clear. I am using "onsubmit" in Form. My input tag is a "type=submit". When the user clicks on this 'submit' button more than once (or presses the "Return" key more than once) I end up with multiple entries. My "onsubmit" goes to a function that checks to see if the input number is valid and if OK the submission is allowed (return true). So, how do I prevent multiple submissions from taking place. There should not be another entry until there is a visible server response to the first submission.