HTML5 with jQuery - e.offsetX is undefined in Firefox

Question

In my HTML5 page, I have a div with mousemove event as follows:

$(\'#canvas\').mousemove(function(e){
    xpos = e.offsetX;
    ypos = e.offsetY         


        

Answer 1

This works fine in firefox and others.

var offsetRequired = (e.offsetX || e.pageX - $(e.target).offset().left);