javascript/jquery - add debounce to a button

george picture george · Nov 8, 2011 · Viewed 24.3k times · Source

I want to add a debounce to a button, but i want to perform some actions each time user clicks button, but only after 5 second after user hits button, then perform SQL update. Usually the throttle seems to be applied directly to the listener. Here I want some actions performed each time the button is clicked, and then an update after a reasonable waiting period.

I am not sure how to use the function in this case...

reference: http://code.google.com/p/jquery-debounce/

$('#myButton').click(function() {
    // do a date calculation
    // show user changes to screen
    // wait until user has has stopped clicking the 
             // button for 5 seconds, then update file with "process" function.

});

function process(){
    // update database table
}

debounce syntax

$('input').bind('keyup blur', $.debounce(process, 5000));

Answer

Felix Kling picture Felix Kling · Nov 8, 2011

You could still use $.debounce like so:

// create new scope
(function() {
     // create debounced function
     var dprocess = $.debounce(process, 5000);

     // bind event handler
     $('#myButton').click(function() {
         // do a date calculation
         // show user changes to screen
         // call the function
         dprocess();
     });
}());

Alternative without $.debounce (you can always debounce your code this way, without jQuery):

// create new scope
(function() {
     var timer;

     // bind event handler
     $('#myButton').click(function() {
         if(timer) {
             clearTimeout(timer);
         }
         // do a date calculation
         // show user changes to screen
         // call the function
         timer = setTimeout(process, 5000);
     });
}());