What is the best way to trim() in javascript

Question

The question says it all; JS doesn\'t seem to have a native trim() method.

Answer 1

Why not just modify the String prototype? Why not steal the trim function from an open source library, like I did here with YUI? (Do you really need to load and entire framework for this simple taks?) Put them together and you get this:

String.prototype.trim = function() {
    try {
        return this.replace(/^\s+|\s+$/g, "");
    } catch(e) {
        return this;
    }
}

var s = " hello ";
alert(s.trim() == "hello"); // displays true

Answer 2

I use this.

    String.prototype.trim = function() {
        return this.replace(/^\s+|\s+$/g,"");
    }

Answer 3

A slightly tinier version of @Pat's.

return str.replace( /^\s+|\s+$/g, '' );

Answer 4

I know this question is ancient but now, Javascript actually does have a native .trim()

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/Trim

Answer 5

Actually, with jQuery this seems to be the way:

jQuery.trim(string)

(Reference)

Answer 6

Well, as a lot of people always says, the trim function works pretty well, but if you don't want to use a whole framework just to perform a trim, it may be useful to take a look at its implementation. So here it is:

function( text ) { return (text || "").replace( /^(\s|\u00A0)+|(\s|\u00A0)+$/g, "" );}

The main advantages I see in this implementation, comparing to other solution already proposed here are:

• The 'g' flag that allows you to perfom a trim on a multi-line string
• The (text || "") syntax that ensure that the function will always work, even if the argument passed is null or undefined.