Access of undefined property URLRequestMethod.POST

Guys what have I been doing wrong? Kindly help it keeps throwing errors. Here's my script:

package{
import flash.display.MovieClip;
import flash.net.FileFilter;
import flash.events.MouseEvent;
import flash.net.FileReference;
import flash.events.MouseEvent;
import flash.events.Event;
import flash.net.URLRequest;
import flash.net.URLVariables;


public class Main extends MovieClip{

    private  var filefilter:FileFilter= new FileFilter("Images (*.jpg, *.jpeg, *.gif, *.png)", "*.jpg; *.jpeg; *.gif; *.png");
    private var filename:String="";
    private var randomname:String;
    private var fileType:Array=new Array(filefilter);
    private var fileref:FileReference;

    public function Main(){


        uploadbtn.addEventListener(MouseEvent.MOUSE_UP, upload)




    }//public  function


private function upload(e:MouseEvent){
    randomname=String(Math.ceil(Math.random()*10000))
    trace(randomname)
    fileref=new FileReference()
    fileref.addEventListener(Event.SELECT,selectHandler);
    fileref.addEventListener(Event.CANCEL,cancelHandler);
    fileref.addEventListener(Event.COMPLETE,completeHandler);
    fileref.browse(fileType);

}//upload

private function selectHandler(e:Event){
    var urlrequest:URLRequest = new URLRequest("http://localhost/upload.php")
    var urlvariable:URLVariables=new URLVariables()

    urlvariable.randomname = randomname;
    urlrequest.data = urlvariable;
    urlrequest.method= URLReque开发者_Python百科stMethod.POST;


}

private function cancelHandler(e:Event){

}


private function completeHandler(e:Event){

}


}// public class

}//package

Did you try also importing URLRequestMethod

import flash.net.URLRequestMethod;