欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页

JQuery Ajax局部刷新功能

程序员文章站 2022-06-17 11:51:07
...

直接通过一个案例来说明一下Ajax和JQuery的基本用法吧,用户注册时,判断当前用户名是否可用,通过弹窗的形式来通知用户,如果用户起的名字为skh则不允许注册,否则可以,就不加数据库来测试了,太麻烦.....

Servlet:

package cn.skh.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class AjaxServlet
 */
@WebServlet("/AjaxServlet")
public class AjaxServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public AjaxServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String test = request.getParameter("test");
		PrintWriter out = response.getWriter();
		if("skh".equals(test) ) {
			out.print("false");
		}else {
			out.print("true");
		}
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

前端JSP:

tips:需要注意的就是$.ajax的格式,以及所需要的参数。

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
<script type="text/javascript" src="scripts/jquery-1.8.3.js"></script>
<script type="text/javascript">
$(document).ready(function(){
    //给账号文本框绑定失去焦点的事件
   $("#test").blur(function(){
       var test=$("#test").val();
       var msg1={
        		"test":test,
        };
       $.ajax({
            url:"AjaxServlet",//设置服务器地址,即为servlet配置的url-pattern
            type:"post",//提交的方式
            data:msg1,//提交到服务器的数据,多个值以逗号分割开
            datatype:"text",
            success:function(msg){//回调函数,msg是返回的数据
           	 if(msg=="false")
				{ 
           		 alert("flase");
           		 
				}
			else{ 
				alert("true");
				
			}
			}
            }); 
    });
});
</script>
</head>
<body>
     
     用户名:<input id="test" type="text" maxlength="20">
     <br>
     密码:<input type="text">
</body>
</html>

结果是没问题的,感兴趣的可以自己去验证一下,这里就不在贴图了。。。。