Ajax跨域访问bing translator的接口，在url中后面直接加上oncompete=mycallback，但是回调函数却不执行，、、、、、、顺便给解释一下oncomplete，这到底是哪的方法？？？

 <script type="text/javascript">
   function loadXMLDoc(){
	xmlHttpRequest=null;
	if (window.XMLHttpRequest)
	  {// code for IE7, Firefox, Opera, etc.
	       
	      xmlHttpRequest=new XMLHttpRequest();
	  }
	else if (window.ActiveXObject)
	  {// code for IE6, IE5
	      xmlHttpRequest=new ActiveXObject("Microsoft.XMLHTTP");
	  }
	 if (xmlHttpRequest!=null)
	  {   
	      xmlHttpRequest.open("GET","AjaxSer",true); 
	      xmlHttpRequest.onreadystatechange=state_Change;
	      xmlHttpRequest.send(null);
	  }
     else
	  {
	    alert("Your browser does not support XMLHTTP.");
	  }
     function state_Change()
        {  
           if(xmlHttpRequest.readyState == 4 && xmlHttpRequest.status == 200){
          
            var responseText = xmlHttpRequest.responseText;
            var from = "en", to = "Zh-CHS", text = "i love you , China";

            var s = document.createElement("script");
            
            s.src = "http://api.microsofttranslator.com/V2/Ajax.svc/Translate" +
                "?appId=Bearer " + encodeURIComponent(responseText) +
                "&from=" + encodeURIComponent(from) +
                "&to=" + encodeURIComponent(to) +
                "&text=" + encodeURIComponent(text) +
                "&oncomplete=mycallback";
             document.body.appendChild(s);
            
            }
        }

       function mycallback(r){
          alert(r);
          document.getElementById("p2").innerHTML = r ;
       }
          
   }
     </script>