js 读取URL参数

var p = new ParamManager();

p.GetValue('key');

        function ParamManager()
        {
            this.Location = window.location;
            this.ParamArray = new Array();
            this.onInit();
        }
        ParamManager.prototype.onInit=function(){
        
            var l = new String(this.Location);
            var paramstring = new String(l.substring(l.lastIndexOf('?')+1,l.length));
            this.ParamArray = paramstring.split('&');
            for(var i = 0;i<this.ParamArray.length;i++)
            {
                this.ParamArray[i] = this.ParamArray[i].toString().split('=');
            }
       
        }
        ParamManager.prototype.GetValue=function(key){
           for(var i=0;i<this.ParamArray.length;i++)
           {
                if(this.ParamArray[i][0] == key)
                {
                    return this.ParamArray[i][1];
                }
           }
           return "null";
        }