//创建XMLHttpRequest对象
    function createXMLHttpRequest() {
		 var XMLHttpReq = false;
		if(window.XMLHttpRequest) { //Mozilla 浏览器
			XMLHttpReq = new XMLHttpRequest();
		}
		else if (window.ActiveXObject) { // IE浏览器
			try {
				XMLHttpReq = new ActiveXObject("Msxml2.XMLHTTP");
			} catch (e) {
				try {
					XMLHttpReq = new ActiveXObject("Microsoft.XMLHTTP");
				} catch (e) {}
			}
		}
		return XMLHttpReq;
	}

    //发送请求函数
    function sendRequest(XMLHttpReq,url,processResponse) {
      XMLHttpReq.open("GET", url, true);
      XMLHttpReq.setRequestHeader("CONTENT-TYPE","application/x-www-form-urlencoded;text/xml;charset=GBK");
      XMLHttpReq.onreadystatechange = processResponse;//指定响应函数
      XMLHttpReq.send(null);  // 发送请求
    }

//判断是否是否空值
function IsNodeValue(parentNode,childNode){
  return !parentNode.getElementsByTagName(childNode)[0].hasChildNodes();
}