Ajax以post方式传送带参的数据方式与get请求的不同

若发送带参数的post请求时必须加上下面这段代码告知服务器将会有参数传过来，不然后台用request.getParameter()将无法获取。

要用getreader()或getInputStream()获取了。

xmlhttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded");

发送同步的Ajax具体代码如下：

function checkRegistedTime() {
var xmlhttp;
if (window.XMLHttpRequest) {
xmlhttp = new XMLHttpRequest;
} else {
xmlhttp = new ActiveObject("Microsoft.XMLHTTP");
}
var registedday = document.getElementById("registeddayDataBase").value;
var registedtime = document.getElementById("registedtime").value;
/* var url = "registedTime_validate.jsp?registedday=" + registedday
+ "®istedtime=" + registedtime; */
var url = "registedTime_validate.jsp";
var data = "registedday=" + registedday + "®istedtime="
+ registedtime;
xmlhttp.open("post", url, false);
xmlhttp.setRequestHeader("Content-Type",
"application/x-www-form-urlencoded");
xmlhttp.send(data);
return xmlhttp.responseText;
}

后台获取数据代码registedTime_validate.jsp：

<%
String registeddayDataBase = request.getParameter("registeddayDataBase");
String registedtime = request.getParameter("registedtime");
%>