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js method to receive and convert array objects in Java

高洛峰
高洛峰Original
2017-01-14 10:45:291470browse

When working on a project, if you want to issue commands to the ocx control, you must get the object in java in js, then put it into a format and send it out. . . It's simple when the object is one, but it's a little more troublesome when the object is an array.

At first I thought there was a simple way to convert the content directly, but later I found out that it was not possible. It was said online that there is no bridge between js and java, so:

My solution is : In the action layer, convert the java object array into a Json string, and in js, convert the json into an array object.

1. Convert the java object array into a Json string:

Two classes are needed:

net.sf.json.JSONObject
net.sf.json.JSONArray
 
 
//将每个vehicle对象拼接为json格式的对象,用于命令下发
JSONObject json = JSONObject.fromObject(v); //v即对象
jsonArray.add(json);
//System.out.println(jsonArray.toString());
//用于命令下发
sendCommandList = jsonArray.toString();

Put them in the for loop middle.

2.js converts it into an object array:

//注意:此时得到的是Json串。
 
//注意:要加上escapeJavaScript="false" escape="false" ,否则传过来Json字符串中的引号都会被解析成为"
 
var szJsonStr = &#39;<s:property escapeJavaScript="false" escape="false" value="sendCommandList" />&#39;;

Finally:

//把Json字符串转化为对象数组
var addVehicleArray = eval(szJsonStr);

When using it, just use addVehicleArray[i].vehicleType;. . . . . .

Extension:

Use of JSONObject and JSONArray

1.JAR package introduction

To make the program run, the JSON-lib package must be introduced, JSON- The lib package also depends on the following JAR package:

commons-lang.jar
commons-beanutils.jar
commons-collections.jar
commons-logging.jar
ezmorph.jar
json-lib-2.2.2-jdk15.jar

2.JSONObject object uses

The JSON-lib package is a beans, collections, maps, java arrays and A package for converting XML and JSON to and from each other. In this example, we will create JSONObject objects using the JSONObject class and then we print the values ​​of these objects. In order to use JSONObject objects, we need to introduce the "net.sf.json" package. To add elements to an object, we use the put() method.

2.1.Example 1

package jsontest;
 
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
 
 
public class JSONObjectSample {
 
 
  // 创建JSONObject对象
  private static JSONObject createJSONObject() {
    JSONObject jsonObject = new JSONObject();
    jsonObject.put("username", "huangwuyi");
    jsonObject.put("sex", "男");
    jsonObject.put("QQ", "413425430");
    jsonObject.put("Min.score", new Integer(99));
    jsonObject.put("nickname", "梦中心境");
    return jsonObject;
  }
 
 
  public static void main(String[] args) {
    JSONObject jsonObject = JSONObjectSample.createJSONObject();//静待方法,直接通过类名+方法调用
    // 输出jsonobject对象
    System.out.println("jsonObject:" + jsonObject);
 
 
    // 判读输出对象的类型
    boolean isArray = jsonObject.isArray();
    boolean isEmpty = jsonObject.isEmpty();
    boolean isNullObject = jsonObject.isNullObject();
    System.out.println("是否为数组:" + isArray + ", 是否为空:" + isEmpty
        + ", isNullObject:" + isNullObject);
 
 
    // 添加属性,在jsonObject后面追加元素。
    jsonObject.element("address", "福建省厦门市");
    System.out.println("添加属性后的对象:" + jsonObject);
 
 
    // 返回一个JSONArray对象
    JSONArray jsonArray = new JSONArray();
    jsonArray.add(0, "this is a jsonArray value");
    jsonArray.add(1, "another jsonArray value");
    jsonObject.element("jsonArray", jsonArray);
    //在jsonObject后面住家一个jsonArray
    JSONArray array = jsonObject.getJSONArray("jsonArray");
    System.out.println(jsonObject);
     
     
    System.out.println("返回一个JSONArray对象:" + array);
    // 添加JSONArray后的值
    // {"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市","jsonArray":["this is a jsonArray value","another jsonArray value"]}
    System.out.println("结果=" + jsonObject);
 
 
    // 根据key返回一个字符串
    String username = jsonObject.getString("username");
    System.out.println("username==>" + username);
 
 
    // 把字符转换为 JSONObject
    String temp = jsonObject.toString();
    JSONObject object = JSONObject.fromObject(temp);
    // 转换后根据Key返回值
    System.out.println("qq=" + object.get("QQ"));
 
 
  }
 
 
}

Output result

jsonObject:{"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境"}
是否为数组:false, 是否为空:false, isNullObject:false
添加属性后的对象:{"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市"}
{"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市","jsonArray":["this is a jsonArray value","another jsonArray value"]}
返回一个JSONArray对象:["this is a jsonArray value","another jsonArray value"]
结果={"username":"huangwuyi","sex":"男","QQ":"413425430","Min.score":99,"nickname":"梦中心境","address":"福建省厦门市","jsonArray":["this is a jsonArray value","another jsonArray value"]}
username==>huangwuyi
qq=413425430

2.2.Example 2.

package jsontest;
 
 
import net.sf.json.JSONArray;
import net.sf.json.JSONObject;
 
 
public class JSONTest {
  public static void main(String args[])
  {
    JSONObject jsonObj0 = new JSONObject();
    JSONObject jsonObj = new JSONObject();
    JSONObject jsonObj2 = new JSONObject();
    JSONObject jsonObj3 = new JSONObject();
    JSONArray jsonArray = new JSONArray();
     
    //创建jsonObj0
    jsonObj0.put("name0", "zhangsan");
    jsonObj0.put("sex1", "female");
    System.out.println("jsonObj0:"+jsonObj0);
     
    //创建jsonObj1
    jsonObj.put("name", "xuwei");
    jsonObj.put("sex", "male");
    System.out.println("jsonObj:"+jsonObj);
   
    //创建jsonObj2,包含两个条目,条目内容分别为jsonObj0,jsonObj1
    jsonObj2.put("item0", jsonObj0);
    jsonObj2.put("item1", jsonObj);
    System.out.println("jsonObj2:"+jsonObj2);
     
    //创建jsonObj3,只有一个条目,内容为jsonObj2
    jsonObj3.element("j3", jsonObj2);
    System.out.println("jsonObj3:"+jsonObj3);
   
    //往JSONArray中添加JSONObject对象。发现JSONArray跟JSONObject的区别就是JSONArray比JSONObject多中括号[]
    jsonArray.add(jsonObj);
    System.out.println("jsonArray:"+jsonArray);
     
    JSONObject jsonObj4 = new JSONObject();
    jsonObj4.element("weather", jsonArray);
    System.out.println("jsonObj4:"+jsonObj4);
  }
}

Output result:

jsonObj0:{"name0":"zhangsan","sex1":"female"}
 
jsonObj:{"name":"xuwei","sex":"male"}
 
jsonObj2:{"item0":{"name0":"zhangsan","sex1":"female"},"item1":{"name":"xuwei","sex":"male"}}
 
jsonObj3:{"j3":{"item0":{"name0":"zhangsan","sex1":"female"},"item1":{"name":"xuwei","sex":"male"}}}
 
jsonArray:[{"name":"xuwei","sex":"male"}]
 
jsonObj4:{"weather":[{"name":"xuwei","sex":"male"}]}

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