String.prototype.trim = function()
 {
   return this.replace(/(^[\s\n\r]*)|([\s\n\r]*$)/g, "");
 }

 String.prototype.ltrim = function()
 {
   return this.replace(/(^\s*)/g, "");
 }

 String.prototype.rtrim = function()
 {
   return this.replace(/(\s*$)/g, "");
 }
 
 String.prototype.isEmpty = function()
 {
   return (this.trim() == "");
 }
 
 String.prototype.isEmail = function()
 {
   return (this.trim() == "");
 }
 
 String.prototype.isHttpURL = function()
 {
   return (this.trim() == "");
 }
 
 String.prototype.isWwwURL = function()
 {
   return (this.trim() == "");
 }
 
 String.prototype.isInteger = function()
 {
   return (this.trim() == "");
 }
 
 String.prototype.isFloat = function()
 {
   return (this.trim() == "");
 }