Ajax异步测试

使用Ajax完成异步请求，对其使用有一个简单的认识

1.完成两个基本的小功能，效果如下

2.组成非常简单Servlet+jsp

jsp如下

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>



  
    
    
    
    
    	
    	
    	
  
  
  	
测试Ajax异步请求
  	

   	
   	

  	

   	
使用ajax完成用户名校验(丧失焦点后，自动校验)
   	用户名: 
  

3.第一个测试基本请求的Servlet

public class DataServlet extends HttpServlet {
	@Override
	protected void service(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		//设置请求编码格式
		req.setCharacterEncoding("utf-8");
		//设置相应编码格式
		resp.setContentType("text/html;utf-8");
		resp.setCharacterEncoding("utf-8");
		//响应请求结果
		resp.getWriter().write("我是异步返回的数据！");
	}
}

4.第二个用户名校验的Servlet

package com.bjsxt.servlet;

import java.io.IOException;

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

import com.bjsxt.pojo.User;
import com.bjsxt.service.UserService;
import com.bjsxt.serviceImpl.UserServiceImpl;

public class UserServlet extends HttpServlet {
	UserService us = new UserServiceImpl();
	@Override
	protected void service(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		//声明请求编码格式
		req.setCharacterEncoding("utf-8");
		//声明响应编码格式
		resp.setCharacterEncoding("utf-8");
		resp.setContentType("text/html; charset =utf-8");
		//获取请求信息
		String str = req.getParameter("uname");
		//处理请求信息,查询数据库，获取信息
		User userName = us.checkUserInfo(str);
		if (!"".equals(str)) {
			if (userName!=null) {
				//返回处理结果
				resp.getWriter().write("true");
			}else {
				resp.getWriter().write("false");
			}
		}else {
			resp.getWriter().write("empty");
		}
	}
}

5.效果如下