var oXmlHttp;       
function createXMLHttpRequest() {    
  if(window.ActiveXObject) {    
     oXmlHttp = new ActiveXObject("Microsoft.XMLHttp");    
  }    
  else if(window.XMLHttpRequest) {    
     oXmlHttp = new XMLHttpRequest();    
  }    
}    
   
function isFormValid () {    
  var frmMain = document.forms[0];    
  var blnValid = true;    
  for(var i=0;i < frmMain.elements.length;i++) {    
     if(typeof frmMain.elements[i].valid == "boolean") {    
        blnValid = blnValid && frmMain.elements[i].valid;    
     }    
  }    
  return blnValid;    
}    
   
function validateField(oEvent) {    
  oEvent = oEvent || window.event;    
  var txtField = oEvent.target || oEvent.srcElement;    
  createXMLHttpRequest();  
  var randNo = parseInt(Math.random()*999999999);
  oXmlHttp.open("get","./include/checkreg.php?"+ txtField.name + "=" + encodeURIComponent(txtField.value) + "&rand=" + randNo,true);    
    
            var imgError = document.getElementById("img"+txtField.id+"Error");    
            var txtError = document.getElementById("txt"+txtField.id+"Error");    
            var submit2 = document.getElementById("submit2");
            
            txtError.style.display = "none";
            imgError.src="./images/gif-load.gif";
            imgError.style.display = "";
            
  oXmlHttp.onreadystatechange = function () {    
     if (oXmlHttp.readyState == 4) {    
        if (oXmlHttp.status == 200) {
	//alert(oXmlHttp.responseText);
            var arrInfo = oXmlHttp.responseText.split("||");
            
            if (!eval(arrInfo[0])) {    
               imgError.title = arrInfo[1];
               imgError.src="./images/attention.gif";
               imgError.style.display = "";    
               txtError.style.display = "";    
               txtError.innerText = arrInfo[1];    
               txtField.valid = false;  
            } else {    
               imgError.style.display = "none";    
               txtField.valid = true;    
               txtError.style.display = "none";    
            }    
            if (isFormValid()) {_endAction();}
	else {_stopAction();}
        } else {    
            alert("伺服器錯誤");    
        }    
    }    
  };    
  oXmlHttp.send(null);    
}