写javascript时出现"缺少对象"错误,望各位高手指教

Question

排下版先,这样的缩进,是不是漏了什么都看不出来.

Answer 1

<script language="JavaScript" type="text/javascript">
function checkDomain(){
var xmlhttp_request = false; 
try{
    if( window.ActiveXObject ){
    for( var i = 5; i; i-- ){
       try{
           if( i == 2 ){
               xmlhttp_request = new ActiveXObject( "Microsoft.XMLHTTP" );
             }
           else{
               xmlhttp_request = new ActiveXObject( "Msxml2.XMLHTTP." + i + ".0" ); 
               xmlhttp_request.setRequestHeader("Content-Type","text/xml");      
               xmlhttp_request.setRequestHeader("Content-Type","gb2312");
             }
           break;
         }catch(e){ 
            xmlhttp_request = false; 
           }
      }
   }
   else if( window.XMLHttpRequest ){
       xmlhttp_request = new XMLHttpRequest();
       if (xmlhttp_request.overrideMimeType){
           xmlhttp_request.overrideMimeType('text/xml'); 
       }
   }
}
catch(e){
 xmlhttp_request = false; 
}
xmlhttp_request.onreadystatechange = reqChange;
xmlhttp_request.open( "GET", "register/checkDomain?domain="+form1.domain.value,true );
xmlhttp_request.send();
}
function reqChange(){
  if(req.readyState==4){
     if(req.status==200){      }
     else{
        alert("problem");
     }
   }
}

Answer 2

哈哈，不好意思，程序写错了
现已解决