Left() function in Javascript or jQuery

Question

I just want a very handy way to extract the numbers out of a string in Javascript and I am thinking about using jQuery, but I prefer the method that proves to be the simplest. I have requested the "left" attribute of a css block using jQuery like this:

var stuff = $('#block').css("left") 

The result of "stuff" is

1008px 

I just want to get rid of the "px" because I need to do a parseInt of it. What is the best method? If Javascript had a left() function, this would be very simple. Thanks

Answer 1

Just do a parseInt("1008px", 10), it will ignore the 'px' for you.

Answer 2

To answer your other question, you can add a left() function to JavaScript's built-in String prototype class so all other strings will inherit it:

String.prototype.left = function(n) {     return this.substring(0, n); } 

And once you include this you can say:

var num = "1008px".left(4); 

I add helpers like trim and capitalize in a base JavaScript file for these kinds of things.