使用ajax接收后台发送过来的json数据方法

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我们。