var http = createRequestObject();
var DivID = '';

function createRequestObject() { 
   var objAjax; 
   var browser = navigator.appName; 
   if(browser == "Microsoft Internet Explorer"){ 
      objAjax = new ActiveXObject("Microsoft.XMLHTTP"); 
   }else{ 
      objAjax = new XMLHttpRequest(); 
   } 
   return objAjax; 
} 

function getNewContent(myurl, DivName){ 
   DivID = DivName;
   http.open('get',myurl); 
   http.onreadystatechange = updateNewContent; 
   http.send(null);
} 

function updateNewContent(){ 
   if(http.readyState == 4){ 
      document.getElementById(DivID).innerHTML = http.responseText; 
   } 
}

function PostForm(myurl, postStr){ 
 if (http.readyState == 4 || http.readyState == 0) { 
   http.open("POST",myurl,true); 
   http.onreadystatechange = updateLoginContent; 

   http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
   http.setRequestHeader("Content-length", postStr.length);
   http.setRequestHeader("Connection", "close");
   http.send(postStr);
 }
}
function updateLoginContent(){ 
   if(http.readyState == 4){ 
      document.getElementById(DivID).innerHTML = http.responseText; 
   } 
}
function AjaxLogin(myurl, theForm, mydiv) {
 var postStr = theForm.txtlogin.name + "=" + encodeURIComponent( theForm.txtlogin.value );
 var postStr = postStr + '&' + theForm.txtpass.name + "=" + encodeURIComponent( theForm.txtpass.value );
 DivID = mydiv;
 PostForm(myurl, postStr);
}