MyFormData

function MyFormData(){
var data=[];
	this.append=function append(name,value){
	data.push([name.toString(),value.toString()]);
	};
	this.toString=function toString(){
	var ret="";
	encodeURIComponent
	var i=0;
	for(;i<data.length;++i){
		ret+=encodeURIComponent(data[i][0])+"="+encodeURIComponent(data[i][1])+"&";
	}
	if(data.length>0){
	ret=ret.slice(0,-1);
	}
	return ret;
	};
	this.valueOf=function valueOf(){
	  return this.toString();
	};
}