Before and after the string, left, and right Spaces

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

Add a trim method to the String object. You can use it like this in the future:

var s = " abc ";
s = s.trim(); //S is a String and you can use the trim method just defined.
alert(s);