var xmlHttp;
	var operatediv;
	var waitPic="<img src=\"./images/loadings.gif\" alt=\"等待加载\" />";
	var temp_text;
	function ShowRequestPage(div,url,ext)
	{
		operatediv=div;
		document.getElementById(operatediv).innerHTML= waitPic+"";//<font color=\"#00FF00\">Loading...</font>
		CreateXMLHttpRequest();
		xmlHttp.onreadystatechange = handleStateChange;
		temp_url=url+ext+"&time="+new Date().getTime();
		//请求
		xmlHttp.open("GET",temp_url,true);
		//发送,一般默认就好了，可以加true or false
		xmlHttp.send();
	}
	//创建异步请求实例函数
	function CreateXMLHttpRequest()
	{
		//如果是IE浏览器则通过实例化ActiveXObject的新实例创建xmlHttp
		if(window.ActiveXObject)
		{
			xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
		}
		//不是IE
		else
		{
			xmlHttp=new XMLHttpRequest();
		}
	}
	//处理状态函数,
	function handleStateChange()
	{
		if(xmlHttp.readyState==4)
		{
			if(xmlHttp.status==200)
			{
				temp_text=xmlHttp.responseText;
				setTimeout("ViewContent()",1000);
			}
			else
			{
				document.getElementById(operatediv).innerHTML=waitPic+"<font color='#FF0000'>It'S Wrong</font>"
			}
		}
	}
	//请求成功后显示页面
	function ViewContent()
	{
		document.getElementById(operatediv).innerHTML= temp_text;
	}
	function buildSelect(name)
	{  
	if(name==1)
		{
			ShowRequestPage('roomtype','showtype.php?type=',getSelectedValue("liansuo"));
		}
	}
	function getSelectedValue(name){
		var obj=document.getElementById(name);
		return obj.value;      //如此简单，直接用其对象的value属性便可获取到
		}