How to make external file linking in as3

I want to open different format external files(*.wmv, *.mp4, *.pdf, *.ppt, *.doc etc) on click event, I try this for *.wmv but got some error.

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package  {

          import flash.display.SimpleButton;

          import flash.events.MouseEvent;

          import flash.net.navigateToURL;

          import flash.net.URLRequest;

          public class clickbutton extends SimpleButton {

                    public function clickbutton() {

                              this.addEventListener(MouseEvent.CLICK, clickF);

                    }

                    private function clickF(e:MouseEvent):void{

                              var nc:NetConnection = new NetConnection();

                              nc.connect(null);

                              var ns:NetStream = new NetStream(nc);

                              videoPlayer.attachNetStream(ns);

                              var listener:Object = new Object();

                              listener.onMetaData = function(evt:Object):void {};

                              ns.client = listener;

                              ns.play("video_test.wmv");

                    }

          }

}

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Please tell me correct code