Community Learn Tools Library Leisure
search
English
Home > Web Front-end > JS Tutorial > Detailed explanation of the steps to transmit Json and XML data via Ajax (with code)

Detailed explanation of the steps to transmit Json and XML data via Ajax (with code)

php中世界最好的语言
Release： 2018-04-03 15:13:45
Original
1841 people have browsed it

This time I will bring you a detailed explanation of the steps for Ajax transmission of Json and XML data (with code). What are the precautions for Ajax transmission of Json and XML data? The following is a practical case, let’s take a look .

ajax transmits xml data: As long as the data is encapsulated into xml format, the transmission can be achieved. The front-end js uses responseXML to receive xml parameters, and the background reading uses streams and dom4j to parse

Front page

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Ajax XML数据处理演示</title>
<script type="text/javascript">
  //get方式ajax
  function send1(){
   alert("ok");
   var name=document.getElementsByName("name")[0].value;
   var age=document.getElementsByName("age")[0].value;
   var xhr=null;
   if(window.XMLHttpRequest){
    xhr=new XMLHttpRequest();
   }else{
    xhr=new ActiveXObject("Microsoft.XMLHttp");
   }
   var url="<c:url value=&#39;/XmlServlet?name=&#39;/>"+name+"&age="+age;
   //3设置访问方式
   xhr.open("GET", url, true);
   //4设置访问成功返回后的操作
   xhr.onreadystatechange=function(){
    if(xhr.readyState==4){//返回
     if(xhr.status==200){//响应代码正常
      var txt=xhr.responseText;
      alert(txt);
     }
    }
   };
   xhr.send(null);
  }
 </script>
<!-- 前台以xml的格式向服务器发送数据 -->
<script type="text/javascript">
  //post方式ajax
  function send2(){
   alert("222");
   //1创建ajax对象
   var xhr = null;
   if(window.XMLHttpRequest){//高版本
    xhr = new XMLHttpRequest();
   }else{//低版本
    xhr = new ActiveXObject("Microsoft.XMLHttp");
   }
   //2请求地址
   var url = "<c:url value=&#39;/XmlServlet&#39;/>";
   //3设置访问方式
   xhr.open("POST", url, true);
   //4设置访问成功返回后的操作
   xhr.onreadystatechange=function(){
    if(xhr.readyState==4){//返回
     if(xhr.status==200){//响应代码正常
      var xmlObj=xhr.responseXML;
      var users=xmlObj.getElementsByTagName("user");
      for(var i=0;i<users.length;i++){
       var id=users[i].getAttribute("id");
       var name=users[i].childNodes[0].firstChild.data;//xml中的dom模型中的操作方法，和html中有点小差别
       var age=users[i].childNodes[1].firstChild.data;//不能用childNodes["age"]
       alert(id+","+name+","+age);
      }
     }
    }
   };
   var name=document.getElementsByName("name")[0].value;
   var age=document.getElementsByName("age")[0].value;
   var xml="<user><name>"+name+"</name><age>"+age+"</age></user>";
   xhr.send(xml);
  }
 </script>
</head>
<body>
 Name:
 <input type="text" name="name">
 <br /> Age:
 <input type="text" name="age">
 <br />
 <input type="button" value="Get提交" onclick="send1();" />
 <br />
 <input type="button" value="Post提交" onclick="send2()" />
 <br />
</body>
</html>
Copy after login
Copy after login

Backend page

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Ajax XML数据处理演示</title>
<script type="text/javascript">
  //get方式ajax
  function send1(){
   alert("ok");
   var name=document.getElementsByName("name")[0].value;
   var age=document.getElementsByName("age")[0].value;
   var xhr=null;
   if(window.XMLHttpRequest){
    xhr=new XMLHttpRequest();
   }else{
    xhr=new ActiveXObject("Microsoft.XMLHttp");
   }
   var url="<c:url value=&#39;/XmlServlet?name=&#39;/>"+name+"&age="+age;
   //3设置访问方式
   xhr.open("GET", url, true);
   //4设置访问成功返回后的操作
   xhr.onreadystatechange=function(){
    if(xhr.readyState==4){//返回
     if(xhr.status==200){//响应代码正常
      var txt=xhr.responseText;
      alert(txt);
     }
    }
   };
   xhr.send(null);
  }
 </script>
<!-- 前台以xml的格式向服务器发送数据 -->
<script type="text/javascript">
  //post方式ajax
  function send2(){
   alert("222");
   //1创建ajax对象
   var xhr = null;
   if(window.XMLHttpRequest){//高版本
    xhr = new XMLHttpRequest();
   }else{//低版本
    xhr = new ActiveXObject("Microsoft.XMLHttp");
   }
   //2请求地址
   var url = "<c:url value=&#39;/XmlServlet&#39;/>";
   //3设置访问方式
   xhr.open("POST", url, true);
   //4设置访问成功返回后的操作
   xhr.onreadystatechange=function(){
    if(xhr.readyState==4){//返回
     if(xhr.status==200){//响应代码正常
      var xmlObj=xhr.responseXML;
      var users=xmlObj.getElementsByTagName("user");
      for(var i=0;i<users.length;i++){
       var id=users[i].getAttribute("id");
       var name=users[i].childNodes[0].firstChild.data;//xml中的dom模型中的操作方法，和html中有点小差别
       var age=users[i].childNodes[1].firstChild.data;//不能用childNodes["age"]
       alert(id+","+name+","+age);
      }
     }
    }
   };
   var name=document.getElementsByName("name")[0].value;
   var age=document.getElementsByName("age")[0].value;
   var xml="<user><name>"+name+"</name><age>"+age+"</age></user>";
   xhr.send(xml);
  }
 </script>
</head>
<body>
 Name:
 <input type="text" name="name">
 <br /> Age:
 <input type="text" name="age">
 <br />
 <input type="button" value="Get提交" onclick="send1();" />
 <br />
 <input type="button" value="Post提交" onclick="send2()" />
 <br />
</body>
</html>
Copy after login
Copy after login

-------------------------------- --------------------------------------------------

The key points of Ajax transmission of Json dataUse Apache or Alibaba's JSONArray class for transmission
Front-end code

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Ajax Json数据处理演示</title>
<script type="text/javascript">
 function ask1() {
  //1创建ajax对象
  var xhr = null;
  if (window.XMLHttpRequest) {//高版本
   xhr = new XMLHttpRequest();
  } else {//低版本
   xhr = new ActiveXObject("Microsoft.XMLHttp");
  }
  //2请求地址
  var url = "<c:url value=&#39;/JsonServlet1&#39;/>";
  //3设置访问方式
  xhr.open("POST", url, true);
  //4设置访问成功返回后的操作
  xhr.onreadystatechange = function() {
   if (xhr.readyState == 4) {//返回
    if (xhr.status == 200) {//响应代码正常
     //※※※※※解析后台返回的json串
     //js中eval()方法的功能：是校验参数文本串符合js中哪一种数据类型，并把其转换成对应类型的对象
     var txt = xhr.responseText;
     var users = eval("(" + txt + ")"); //把符合json格式的文本串 转换成 json对象
     for ( var i = 0; i < users.length; i++) {
      alert(users[i].id + "," + users[i].name + ","
        + users[i].age);
     }
    }
   }
  };
  //5 发送
  xhr.send(null);
 }
 function ask2() {
  //1创建ajax对象
  var xhr = null;
  if (window.XMLHttpRequest) {//高版本
   xhr = new XMLHttpRequest();
  } else {//低版本
   xhr = new ActiveXObject("Microsoft.XMLHttp");
  }
  //2请求地址
  var url = "<c:url value=&#39;/JsonServlet2&#39;/>";
  //3设置访问方式
  xhr.open("POST", url, true);
  //4设置访问成功返回后的操作
  xhr.onreadystatechange = function() {
   if (xhr.readyState == 4) {//返回
    if (xhr.status == 200) {//响应代码正常
     //※※※※※解析后台返回的json串
     //js中eval()方法的功能：是校验参数文本串符合js中哪一种数据类型，并把其转换成对应类型的对象
     var txt = xhr.responseText;
     //alert(txt);
     //把符合json格式的文本串 转换成 json对象
     var users = eval("(" + txt + ")"); 
     for ( var key in users)//map的便利方式
      alert("属性：" + key + ",值：" + users[key]);
     }
     //for ( var i = 0; i < users.length; i++) {//list的遍历方式
      //alert(users[i].id +","+users[i].name+","+users[i].age);
     //}
   };
  };
  //5 发送
  xhr.send(null);
 }
 function ask3() {
  //1创建ajax对象
  var xhr = null;
  if (window.XMLHttpRequest) {//高版本
   xhr = new XMLHttpRequest();
  } else {//低版本
   xhr = new ActiveXObject("Microsoft.XMLHttp");
  }
  //2请求地址
  var url = "<c:url value=&#39;/JsonServlet2&#39;/>";
  //3设置访问方式
  xhr.open("POST", url, true);
  //4设置访问成功返回后的操作
  xhr.onreadystatechange = function() {
   if (xhr.readyState == 4) {//返回
    if (xhr.status == 200) {//响应代码正常
     //※※※※※解析后台返回的json串
     //js中eval()方法的功能：是校验参数文本串符合js中哪一种数据类型，并把其转换成对应类型的对象
     var txt = xhr.responseText;
     //alert(txt);
     //把符合json格式的文本串 转换成 json对象
     var users = eval("(" + txt + ")"); 
     for ( var key in users)//map的便利方式
      alert("属性：" + key + ",值：" + users[key]);
     }
     //for ( var i = 0; i < users.length; i++) {//list的遍历方式
      //alert(users[i].id +","+users[i].name+","+users[i].age);
     //}
   };
  };
  //5 发送
  xhr.send(null);
 }
</script>
</head>
<body>
 <input type="button" onclick="ask1();" value="ajax请求后台数据(手动封装json方式)" />
 <br />
 <input type="button" onclick="ask2();"
  value="ajax请求后台数据(用apache工具封装json方式)" />
 <input type="button" onclick="ask3()" value="ajax请求后台数据(用fastjson工具封装json方式)" />
</body>
</html>
Copy after login

JsonServlet1.java

package cn.hncu.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.hncu.domain.User;
public class JsonServlet1 extends HttpServlet {
 public void doGet(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  doPost(request, response);
 }
 public void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  //调用后台service.dao.query()，到数据库当中把信息读取出来
  //为简化知识点的理解，此处后台部分的功能直接模拟
  response.setContentType("text/html;charset=utf-8");
  PrintWriter out = response.getWriter();
  List<User> users = new ArrayList<User>();
  users.add(new User("A001","Jack",20));
  users.add(new User("A002","Rose",22));
  users.add(new User("B001","张三",20));
  users.add(new User("B002","李四",30));
  String json="";
  //用java封装出json格式的字符串：[{name:"Jack",age:25}, {...}, {...} ]
  for(User u:users){
   if(json.equals("")){
    json="{name:\""+u.getName()+"\",id:\""+u.getId()+"\",age:"+u.getAge()+"}";
   }else{
    json = json +",{ name:\""+u.getName()+"\",id:\""+u.getId()+"\",age:"+u.getAge()+"}" ;
   }
  }
  json="["+json+"]";
  out.print(json);
 }
}
Copy after login

JsonServlet2.java

package cn.hncu.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.hncu.domain.User;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
public class JsonServlet2 extends HttpServlet {
 public void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  response.setContentType("text/html;charset=utf-8");
  PrintWriter out = response.getWriter();
  List<User> users = new ArrayList<User>();
  users.add(new User("A001","Jack",20));
  users.add(new User("A002","Rose",22));
  users.add(new User("B001","张三",20));
  users.add(new User("B002","李四",30));
  String strJson=com.alibaba.fastjson.JSONArray.toJSONString(users);
  System.out.println(strJson);
  //用fastjson工具(只有一个jar包)帮我们把list转换成json串
  Map<String, Object> map = new HashMap<String, Object>();
  map.put("addr", "湖南");
  map.put("height", "170");
  map.put("marry", "no");
  map.put("user", new User("A003","小李",25));
  String strMap=com.alibaba.fastjson.JSONArray.toJSONString(map);
  out.print(strMap.toString());
 }
}
Copy after login

JsonServlet3.java

package cn.hncu.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
import cn.hncu.domain.User;
public class JsonServlet3 extends HttpServlet {
 public void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
  response.setContentType("text/html;charset=utf-8");
  PrintWriter out = response.getWriter();
  List<User> users = new ArrayList<User>();
  users.add(new User("A001","Jack",20));
  users.add(new User("A002","Rose",22));
  users.add(new User("B001","张三",20));
  users.add(new User("B002","李四",30));
  //用fastjson工具(只有一个jar包)帮我们把list转换成json串
  JSONArray json=JSONArray.fromObject(users);
  String strJson=json.toString();
  System.out.println(strJson);
  Map<String, Object> map = new HashMap<String, Object>();
  map.put("addr", "湖南");
  map.put("height", "170");
  map.put("marry", "no");
  map.put("user", new User("A003","小李",25));
  JSONObject obj = JSONObject.fromObject(map);
  System.out.println(obj.toString());
  out.print(obj.toString());
 }
}
Copy after login

I believe you have mastered the method after reading the case in this article. For more exciting information, please pay attention to other related articles on the PHP Chinese website!

Recommended reading:

How does ajax submit a form and implement file upload

Ajax transmits json format data to the background. How to handle errors

The above is the detailed content of Detailed explanation of the steps to transmit Json and XML data via Ajax (with code). For more information, please follow other related articles on the PHP Chinese website!

Related labels：
ajax javascript json
source：php.cn
Previous article：Ajax upload and preview images (with code) Next article：PHP commonly used small functions
Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Latest Articles by Author
Latest Issues
CSS only method to dynamically modify image src on click without using JavaScript I need to change the src of an image on mouse click using only css like img:active{}
From 2024-04-06 19:25:49
0
1
505
Scatterplot points do not maintain values ​​when zooming in d3.js This is my first time using d3.js, so please bear with me. I implemented it as pure JavaSc...
From 2024-04-06 18:16:26
0
1
403
JavaScript hover events on vendor-specific pseudo-elements I have the following htmlinput tag. $("input[type='range']::-webkit-slider-thumb"...
From 2024-04-06 15:35:24
0
1
274
Submit form without button using Javascript/Jquery I'm trying to submit a form without a button by calling a JavaScript function and executin...
From 2024-04-06 14:54:03
0
2
421
Customize the appearance of Bootstrap accordion headers using the CollapseDisplay class I want to style the card title of a panel with class collapseshow. In this example, it's t...
From 2024-04-06 12:53:11
0
1
376
Related Topics
More>
Popular Recommendations
Popular Tutorials
More>
Related Tutorials
Popular Recommendations
Latest courses
Latest Downloads
More>
Web Effects
Website Source Code
Website Materials
Front End Template