Ajax獲取xmlHTTPRequest代碼

    function getXMLRequester( )
    {    
	    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;   
        }    
        return xmlhttp_request ;
    }