Detailed explanation of the steps to transmit Json and XML data via Ajax (with code)-JS Tutorial-php.cn

Home

Web Front-end

JS Tutorial

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

php中世界最好的语言

Apr 03, 2018 pm 03:13 PM

ajax javascript json

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

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

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

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!

Hot AI Tools

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress images for free

Clothoff.io

AI clothes remover

AI Hentai Generator

Generate AI Hentai for free.

Hot Article

R.E.P.O. Energy Crystals Explained and What They Do (Yellow Crystal)

3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

R.E.P.O. Best Graphic Settings

3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Assassin's Creed Shadows: Seashell Riddle Solution

2 weeks ago By DDD

R.E.P.O. How to Fix Audio if You Can't Hear Anyone

3 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

WWE 2K25: How To Unlock Everything In MyRise

4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

Hot Tools

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Where is the login entrance for gmail email?

7476

CakePHP Tutorial

1377

What is the format of the account name of steam

win11 activation key permanent

nyt connections hints and answers

Related knowledge

Performance optimization tips for converting PHP arrays to JSON May 04, 2024 pm 06:15 PM

Performance optimization methods for converting PHP arrays to JSON include: using JSON extensions and the json_encode() function; adding the JSON_UNESCAPED_UNICODE option to avoid character escaping; using buffers to improve loop encoding performance; caching JSON encoding results; and considering using a third-party JSON encoding library.

How do annotations in the Jackson library control JSON serialization and deserialization? May 06, 2024 pm 10:09 PM

Annotations in the Jackson library control JSON serialization and deserialization: Serialization: @JsonIgnore: Ignore the property @JsonProperty: Specify the name @JsonGetter: Use the get method @JsonSetter: Use the set method Deserialization: @JsonIgnoreProperties: Ignore the property @ JsonProperty: Specify name @JsonCreator: Use constructor @JsonDeserialize: Custom logic

How to get variables from PHP method using Ajax? Mar 09, 2024 pm 05:36 PM

Using Ajax to obtain variables from PHP methods is a common scenario in web development. Through Ajax, the page can be dynamically obtained without refreshing the data. In this article, we will introduce how to use Ajax to get variables from PHP methods, and provide specific code examples. First, we need to write a PHP file to handle the Ajax request and return the required variables. Here is sample code for a simple PHP file getData.php:

PHP and Ajax: Building an autocomplete suggestion engine Jun 02, 2024 pm 08:39 PM

Build an autocomplete suggestion engine using PHP and Ajax: Server-side script: handles Ajax requests and returns suggestions (autocomplete.php). Client script: Send Ajax request and display suggestions (autocomplete.js). Practical case: Include script in HTML page and specify search-input element identifier.

In-depth understanding of PHP: Implementation method of converting JSON Unicode to Chinese Mar 05, 2024 pm 02:48 PM

In-depth understanding of PHP: Implementation method of converting JSONUnicode to Chinese During development, we often encounter situations where we need to process JSON data, and Unicode encoding in JSON will cause us some problems in some scenarios, especially when Unicode needs to be converted When encoding is converted to Chinese characters. In PHP, there are some methods that can help us achieve this conversion process. A common method will be introduced below and specific code examples will be provided. First, let us first understand the Un in JSON

PHP vs. Ajax: Solutions for creating dynamically loaded content Jun 06, 2024 pm 01:12 PM

Ajax (Asynchronous JavaScript and XML) allows adding dynamic content without reloading the page. Using PHP and Ajax, you can dynamically load a product list: HTML creates a page with a container element, and the Ajax request adds the data to that element after loading it. JavaScript uses Ajax to send a request to the server through XMLHttpRequest to obtain product data in JSON format from the server. PHP uses MySQL to query product data from the database and encode it into JSON format. JavaScript parses the JSON data and displays it in the page container. Clicking the button triggers an Ajax request to load the product list.

PHP Tutorial: How to Convert JSON Unicode to Chinese Characters Mar 05, 2024 pm 06:36 PM

JSON (JavaScriptObjectNotation) is a lightweight data exchange format commonly used for data exchange between web applications. When processing JSON data, we often encounter Unicode-encoded Chinese characters (such as "u4e2du6587") and need to convert them into readable Chinese characters. In PHP, we can achieve this conversion through some simple methods. Next, we will detail how to convert JSONUnico

Quick tips for converting PHP arrays to JSON May 03, 2024 pm 06:33 PM

PHP arrays can be converted to JSON strings through the json_encode() function (for example: $json=json_encode($array);), and conversely, the json_decode() function can be used to convert from JSON to arrays ($array=json_decode($json);) . Other tips include avoiding deep conversions, specifying custom options, and using third-party libraries.

See all articles