chat.js

asp.net +AJAX无刷新聊天室

//ajax
function getObject(objectId) {
     if(document.getElementById && document.getElementById(objectId)) 
     {
       // W3C DOM
       return document.getElementById(objectId);
     } 
     else if (document.all && document.all(objectId)) 
     {
       // MSIE 4 DOM
       return document.all(objectId);
     } 
     else if (document.layers && document.layers[objectId]) 
     {
       // NN 4 DOM.. note: this won't find nested layers
       return document.layers[objectId];
     } 
     else 
     {
       return false;
     }
}  
// CreateXMLHttpRequest
function CreateXMLHttpRequest()
{
   // Initialize Mozilla XMLHttpRequest object
   var xmlHttp;
   if (window.XMLHttpRequest)
   {
       xmlHttp = new XMLHttpRequest();
   } 
   // Initialize for IE/Windows ActiveX version
   else if (window.ActiveXObject)
   {
       try
       {
                xmlHttp = new ActiveXObject("Msxml2.XMLHTTP.3.0");
         } 
       catch (e)
       {
                try
                {
                     xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
                }  
                catch(e)
                {
                     newsstring = "对不起，您的浏览器不支持XMLHttpRequest对象！";}
          }   
   }
   return xmlHttp;
}

function getDataTimes()
{
	var strDate,strTime;
	strDate = new Date();
	strTime = strDate.getTime();
	return strTime;
}

//获取信息
function ShowMess()
{
    var strtime = getDataTimes();
	var url="mess.asp?strTime="+strtime;
	var requestType = "mess_box";
	var xmlHttp=CreateXMLHttpRequest();
    xmlHttp.open("GET", url, true);
	xmlHttp.onreadystatechange = function() 
	{
		if (xmlHttp.readyState == 4 && xmlHttp.status == 200) 
		{
			getObject(requestType).innerHTML  = xmlHttp.responseText;
		}
	}
    xmlHttp.setRequestHeader("If-Modified-Since","0");
    xmlHttp.send(null); 
	$();
	online();
	
}
//发送信息
function SendMess()
{
    var strtime = getDataTimes();
	var mess = escape(document.getElementById('mess').value);
	var mtowho = escape(document.getElementById('mtowho').value);
	var mfont = escape(document.getElementById('mfont').value);
	var mfcolor = escape(document.getElementById('mfcolor').value);
	var elist = escape(document.getElementById('elist').value);
	if (mess=="")
	{
	alert("不能发空信息！");
	return false;
	}
	var url="SendMess.asp?mess="+mess+"&mtowho="+mtowho+"&mfont="+mfont+"&mfcolor="+mfcolor+"&elist="+elist+"&strTime="+strtime;
	var xmlHttp=CreateXMLHttpRequest();
    xmlHttp.open("get", url, true);
    xmlHttp.send(null);  
	ShowMess();
	document.getElementById('mess').value="";

}
//刷新
function getmess()
{
time=window.setInterval("ShowMess()",2000);	
}
//检查是否离开
function $() {
    var strtime = getDataTimes();
	var url="k.asp?strTime="+strtime;
	var xmlHttp=CreateXMLHttpRequest();
    xmlHttp.open("GET", url, true);
	xmlHttp.onreadystatechange = function() 
	{
		if (xmlHttp.readyState == 4 && xmlHttp.status == 200) 
		{
			if (xmlHttp.responseText=="showScreen"){
				showScreen();
				}
		}
	}
    xmlHttp.setRequestHeader("If-Modified-Since","0");
    xmlHttp.send(null);  
}
// 获取宽度
function getWidth()
{
    var strWidth,clientWidth,bodyWidth;
    clientWidth = document.documentElement.clientWidth;
    bodyWidth = document.body.clientWidth;
    if(bodyWidth > clientWidth){
        strWidth = bodyWidth + 20;
    } else {
        strWidth = clientWidth;
    }
    return strWidth;
}
//获取高度
function getHeight()
{
    var strHeight,clientHeight,bodyHeight;
    clientHeight = document.documentElement.clientHeight;
    bodyHeight = document.body.clientHeight;
    if(bodyHeight > clientHeight){
        strHeight = bodyHeight + 30;
    } else {
        strHeight = clientHeight;
    }
    return strHeight;
}
// 锁屏
function showScreen()
{
    var Element = getObject('Message');
    var Elements = getObject('Screen');
    Elements.style.width = getWidth();
    Elements.style.height = getHeight();
    Element.style.display = 'block';
    Elements.style.display = 'block';
	getObject('mfont').disabled   =   true;  
	getObject('mfcolor').disabled   =   true;
	getObject('elist').disabled   =   true;
}
//解屏
function hideScreen()
{
    var Element = getObject('Message');
    var Elements = getObject('Screen');
    Element.style.display = 'none';
    Elements.style.display = 'none';
	getObject('mfont').disabled   =   false;  
	getObject('mfcolor').disabled   =   false;
	getObject('elist').disabled   =   false;

}
//提交名称
function chkuser()
{
	
    var strtime = getDataTimes();
	var userid = escape(document.getElementById('userid').value);
	var ischk;
	if (userid=="")
	{
	alert("请输入名称！");
	return false;
	}
	var url="user.asp?userid="+userid+"&strTime="+strtime;
	var xmlHttp=CreateXMLHttpRequest();
    xmlHttp.open("get", url, true);
	xmlHttp.onreadystatechange = function() 
	{
		if (xmlHttp.readyState == 4 && xmlHttp.status == 200) 
		{
			if (xmlHttp.responseText=="no"){
			getObject("errmeg").innerHTML="你的名称已占用";
			}
			else
			{
			hideScreen();
			}
		}
	}
    xmlHttp.send(null);
}
//显示 在线人数
function online()
{
	
    var strtime = getDataTimes();
	var url="online.asp?strTime="+strtime;
	var xmlHttp=CreateXMLHttpRequest();
	var requestType = "on_line";
    xmlHttp.open("get", url, true);
	xmlHttp.onreadystatechange = function() 
	{
		if (xmlHttp.readyState == 4 && xmlHttp.status == 200) 
		{
			getObject(requestType).innerHTML=xmlHttp.responseText;
		}
	}
   
	xmlHttp.setRequestHeader("If-Modified-Since","0");
	xmlHttp.send(null);

}
//选择对话人
function mtowho(mtowho){
	var requestType="mtowho";
	getObject(requestType).value=mtowho;
}