Struts2——实现ajax、json

骑猪看日落 2022-07-12 00:28 137阅读 0赞

**1、导对包包**

这里是核心包
    commons-fileupload-1.3.2.jar
    commons-io-2.4.jar
    commons-lang3-3.4.jar
    freemarker-2.3.23.jar
    javassist-3.20.0-GA.jar
    log4j-api-2.7.jar
    ognl-3.1.12.jar
    struts2-core-2.5.8.jar
    
    这里是JSON依赖包，(ToT这里可坑哭我了，没导对一直报错...)
    commons-beanutils-1.9.2.jar
    commons-collections-3.2.1.jar
    commons-lang-2.4.jar
    ezmorph-1.0.6.jar
    json-lib-2.3-jdk15.jar
    struts2-json-plugin-2.5.10.jar

**2、struts2实现ajax、json重点在于struts.xml**

1、<package>标签的写法：
    <package name="随意" namespace="/" extends="json-default">
                                    //extends必须继承"json-default"
    </package>

2、<result>标签的写法：
    <result type="json">//type必须写json
                   //不写<param>标签即该action下所有返回的变量
                    <param name="root">要改成json格式的变量</param>
    </result>

**3、其它就和常规一样…举个小栗子**

JsonAction.java

public class JsonAction extends ActionSupport{ 
        private User user;//User类就name、age；
        private JSONArray  jsonArray;
    
        @Override
        public String execute() throws Exception {
            System.out.println("测试数据");
            List<User> list=new ArrayList<User>();
            list.add(new User("小福",17));
            list.add(new User("王优",52));
            list.add(new User("布赫优",34));
            jsonArray=JSONArray.fromObject(list);
            return SUCCESS;
        }
    
        public JSONArray getJsonArray() {
            return jsonArray;
        }
        public void setJsonArray(JSONArray jsonArray) {
            this.jsonArray = jsonArray;
        }
        public User getUser() {
            return user;
        }
    
        public void setUser(User user) {
            this.user = user;
        }
    
    }

struts.xml

<struts>
        <package name="ajax" namespace="/" extends="json-default">
            
            <action name="json" class="com.action.JsonAction" >
                <result type="json">
                    <param name="root">jsonArray</param>
                </result>
            </action>
        </package>
    </struts>

JSON.jsp(用js写的显得很多，jq的话很方便，但是不会)

<html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    <script type="text/javascript"> window.onload=function(){ var bt=document.getElementById("bt"); bt.onclick=function(){ var xmlhttp=new XMLHttpRequest; xmlhttp.open("POST","json"); xmlhttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded"); xmlhttp.send(); xmlhttp.onreadystatechange=function(){ if (xmlhttp.readyState==4) { if (xmlhttp.status==200) { var msg=document.getElementById("msg"); var redata=xmlhttp.responseText.toString(); var myjson=JSON.parse(redata); var text=""; for(var i=0;i<myjson.length;i++){ text+=myjson[i].name+":"; text+=myjson[i].age+", "; } msg.innerHTML=text; } } } } } </script>
    </head>
    
    <body>
    <button id="bt">点我获取JSON</button>
    <h1 id="msg"></h1>
    </body>
    </html>

效果图

![这里写图片描述][SouthEast]  
![这里写图片描述][SouthEast 1]

[SouthEast]: /images/20220711/0b5d9c69c91f4e73a090ca61c1cee01a.png
[SouthEast 1]: /images/20220711/4f75b492c2d5451089c958aea21bef23.png