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

Use Ariel Flesler's fast trim function:

// Licensed under BSD
function myBestTrim( str ){
 var start = -1,
  end = str.length;
 while( str.charCodeAt(--end) < 33 );
 while( str.charCodeAt(++start) < 33 );
 return str.slice( start, end + 1 );
};

My solution, though, would be this (because the String object in Firefox 3.5 and above already has a trim method):

String.prototype.trim = String.prototype.trim || function () {
    var start = -1,
        end   = this.length;

    while( this.charCodeAt(--end) < 33 );
    while( this.charCodeAt(++start) < 33 );

    return this.slice( start, end + 1 );
};