请高手指点 - Web 开发 / Ajax
哪位高手能给一个最简单的AJAX的例子

[解决办法]

CSS code

html:<label for="tbName">Your Name:</label><input id="tbName" name="tbName" type="text" /><input id="btnSayHello" type="button" value="Say Hello From Server!" /><div id="lbMessage"></div>servlet:doPost(request, response) {String name = request.getParmeter("tbName");response.getWriter().print(name);}JS:function print() {var name = document.getElementById("tbName").value;sendRequest("url/servlet?name=" + name, lbMessage);}function sendRequest(url,showAreaId){  var xmlHttp = new XMLHttpRequest();  url += "&sessionId="+parseInt(Math.random()*(10000000));  //alert(url);  xmlHttp.onreadystatechange = function()  {    if(xmlHttp.readyState==4)    {      if(xmlHttp.status==200){      document.getElementById(showAreaId).innerHTML=xmlHttp.responseText;    }    else    {      alert('消息：'+xmlHttp.responseText);      return;    }  } }  xmlHttp.open("GET",url, false);  xmlHttp.send(null);}