How can I prevent a double submit with jQuery or Javascript?

Question

I keep getting duplicate entries in my database because of impatient users clicking the submit button multiple times.

I googled and googled and found a few scripts,

Answer 1

Preventing the double posting is not so simple as disabling the submit button. There are other elements that may submit it:

• button elements
• img elements
• javascripts
• pressing 'enter' while on some text field

Using jQuery data container would be my choice. Here's an example:

$('#someForm').submit(function(){
    $this = $(this);

    /** prevent double posting */
    if ($this.data().isSubmitted) {
        return false;
    }

    /** do some processing */

    /** mark the form as processed, so we will not process it again */
    $this.data().isSubmitted = true;

    return true;
});