Ajax之json返回结果是集合的处理

缺乏、安全感 2022-01-28 08:15 249阅读 0赞

**Jquery实现ajax：**

$.ajax(\{  
      type    //数据的提交方式：get和post  
       url   //数据的提交路径  
       async   //是否支持异步刷新，默认是true  
       data    //需要提交的数据  
       datatype   //服务器返回数据的类型，例如xml,String,Json等  
       success    //请求成功后的回调函数  
       error   //请求失败后的回调函数\});  
\}  
)

**json对服务器返回结果是集合的处理**

success:function(data)\{成功处理  
            var json = eval('('+data+')'); 将JSON的字符串解析成JSON数据格式    
            var table="<table>";  
            for(var i in json)\{  
 table+="<tr><td>"+json\[0\].id+"</td><td>"+json\[i\].name+"</td><td>"+json\[i\].birthday+"</td><td>"+json\[i\].regTime+"</td></tr>";  
            $("\#show").html(table);显示在页面  
             \}  
            table+="</table>";  
            \},

### **代码实现：** ###

**userList.jsp**

<%--
      Description:ajax 返回集合
      User: jiatp
      Date: 2019/5/22
      Time: 21:45
    --%>
    <%@ page language="java" contentType="text/html; charset=UTF-8"
             pageEncoding="UTF-8" %>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>Insert title here</title>
    </head>
    <script type="text/javascript" src="js/jquery.js"></script>
    <script type="text/javascript">
        //初始化
        $(function () {
                $("#btn").click(function () {
                  $.ajax({
                      type:"post",
                      url:"showAllUserList",
                      data:{},
                      datatype:"json",
                      success:function (data) {
                          //转换为javascript对象
                          var user = eval('('+data+')');
                          var str = "<table>";
                          var strcontent = "";
                          for(var i=0;i<user.length;i++){
                              strcontent+="<tr><td>"+user[i].id+"</td><td>"+user[i].name+"</td><td>"+user[i].address+"</td></tr>"
                          }
                          str+=strcontent+"</table>";
                          $("#content").html(str);
                      },error:function () {
                       alert("error!");
                      }
                  })
                })
        })
    </script>
    <body>
    <input type="button" id="btn" value="显示集合">
    <div id="content"></div>
    </body>
    </html>

### **showAllUserList.java** ###

package com.chinasofti.servlet;
    
    import com.chinasofti.entity.User;
    import net.sf.json.JSONArray;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import java.io.IOException;
    import java.io.PrintWriter;
    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * Description:ajax返回一个集合对象
     * USER:jiatp
     * Date:2019/5/22 22:16
     * */
    @WebServlet("/showAllUserList")
    public class showAllUserList extends HttpServlet {
        protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
            response.setContentType("text/html;charset=utf-8");
            request.setCharacterEncoding("utf-8");
    
            List<User> userList = new ArrayList();
    
            User user1 = new User();
            user1.setName("张三");
            user1.setAddress("北京");
            user1.setId(1);
            User user2 = new User();
            user2.setName("李四");
            user2.setAddress("上海");
            user2.setId(2);
            //添加到集合
            userList.add(user1);
            userList.add(user2);
            PrintWriter out = response.getWriter();
            //将user对象转换成json格式
            JSONArray json = JSONArray.fromObject(userList);
            System.out.println(json);
            out.print(json);
        }
    
        protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
            doPost(request,response);
        }
    }

**注：**var json = eval('('+data+')'); 将JSON的字符串解析成JSON数据格式