Ajax学习笔记(四)

来源：互联网发布：天刀捏脸数据女清纯编辑：程序博客网时间：2024/06/08 07:12

验证日期合法性的例子:

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title></title>
<script type="text/javascript">
var xmlHttp;
function createXMLHTTPRequest()
{
    if(window.ActiveXObject)
    {
      xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
    else if(window.XMLHttpRequest)
    {
      xmlHttp=new XMLHttpRequest();
    }
}
function validate()
{
    createXMLHTTPRequest();
    var date=document.getElementById("birthDate");
    var url="PostData?birthDate="+escape(date.value)+"&timeStamp="+(new Date()).getTime();
    xmlHttp.open("Get",url,true);
    xmlHttp.onreadystatechange=handleStateChange;
    xmlHttp.send(null);
}
function handleStateChange()
{

    if(xmlHttp.readyState==4)
    {
      if(xmlHttp.status==200)
      {
        var msg=xmlHttp.responseXML.getElementsByTagName("message")[0].firstChild.nodeValue;
        var val=xmlHttp.responseXML.getElementsByTagName("passed")[0].firstChild.nodeValue;
        setMessage(msg,val);
      }
    }
}
function setMessage(message,isValid)
{
    var messageArea=document.getElementById("dateMessage");
    var fontColor="red";
    if(isValid=="true")
    {
        fontColor="green";
    }
    messageArea.innerHTML="<font color="+fontColor+">"+message+"</font>";
}
</script>
</head>
<body>
<form action="#">

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@

import java.io.*;
import java.net.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.text.SimpleDateFormat;

public class PostData extends HttpServlet
{
protected void doGet(HttpServletRequest req,HttpServletResponse res)throws ServletException,IOException
{
  doPost(req,res);
}
protected void doPost(HttpServletRequest req,HttpServletResponse res)throws ServletException,IOException
{
  req.setCharacterEncoding("UTF-8");
  String passed=req.getParameter("birthDate");
  res.setContentType("text/xml");
  res.setHeader("Cache-Control","no-cache");
  String message="非法的日期!";
  boolean isValid=true;
  if(passed!=null)
  {
   SimpleDateFormat sdf=new SimpleDateFormat("MM/dd/yyyy");
   try
   {
    sdf.parse(passed);
   }
   catch(Exception e)
   {

    isValid=false;
   }
  }
  else
  {
   isValid=false;
  }

  if(isValid)
  {
   message="日期合法!";
  }
  res.setCharacterEncoding("UTF-8");
  res.getWriter().print("<response><passed>"+Boolean.toString(isValid)+"</passed><message>"+message+"</message></response>");
}
}