时间：2021-07-01 10:21:17 帮助过：16人阅读
今天给大家带来一个简单的使用ajax接收后台返回json格式的demo
废话不多说直接上代码
后台代码
package com.sidan.outjson;
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;
import com.sidan.jsonutil.GetJson;
/**
* Servlet implementation class OutJson
*/
@WebServlet("/OutJson")
public class OutJson extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public OutJson() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doPost(request,response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setCharacterEncoding("UTF-8");
PrintWriter out = response.getWriter();
String s = GetJson.getJson();
out.print(s);
}
}
Pserson类
package com.sidan.jsonutil;
public class Person {
private String name;
private String sex;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
将数据包装成json格式类（数据直接是循环添加的所以一样这里是为了简单）
package com.sidan.jsonutil;
import java.util.ArrayList;
public class GetJson {
public static String getJson(){
return json().toString();
}
public static StringBuffer json(){
StringBuffer sb = new StringBuffer();
ArrayList<Person> arr = initArray();
int x = 0;
sb.append("[");
for(Person p:arr){
sb.append("{");
sb.append("\"name\"");
sb.append(":");
sb.append("\""+p.getName()+"\"");
sb.append(",");
sb.append("\"age\"");
sb.append(":");
sb.append("\""+p.getAge()+"\"");
sb.append(",");
sb.append("\"sex\"");
sb.append(":");
sb.append("\""+p.getSex()+"\"");
sb.append("}");
if(x != arr.size()-1){
sb.append(",");
}
x++;
}
sb.append("]");
return sb;
}
public static ArrayList<Person> initArray(){
ArrayList<Person> arr = new ArrayList<Person>();
for(int i = 0;i < 10;i++){
Person p = new Person();
p.setName("sdchen");
p.setAge(20);
p.setSex("man");
arr.add(p);
}
return arr;
}
}
jsp页面代码
<pre name="code" class="html"><%@ 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=ISO-8859-1">
<title>Insert title here</title>
<script src="jQuery/jquery-3.1.1.min.js"></script>
<script type="text/javascript">
$(function(){
$("#btn").click(function(){
var url = "OutJson";
$.ajax({
url:url,
type:"post",
dataType:"json",
error:function(XMLHttpRequest, textStatus, errorThrown){
alert(XMLHttpRequest);
alert(textStatus);
alert(errorThrown);
},
success:function(data){
$.each(data,function(idx,obj){
var li = document.createElement("li");
li.innerHTML = "<a>" + obj.name + "</a>";
document.getElementById("ul1").appendChild(li);
});
}
});
});
});
</script>
</head>
<body>
<ul id="ul1"></ul>
<input type="button" value="循环" id="btn"/>
</body>
</html>
写这个demo也费了很大劲，毕竟是新手，也从错误中学到了很多，比如dataType写成datatype时ajax默认接收的数据是为text这样导致我总是循环不了,还有就是json数据的格式是非常严谨的
就因为最后多了一个逗号就导致总是出错，并且循环不了，最后将错误打印出来才知道这个格式是错了的
以上这篇使用ajax接收后台发送过来的json数据方法就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持脚本之家。