Android操作Json

第一種用Android自帶的 org.Json包

package Test.action;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
//用之前先把org.json包裏面的類 全部放到項目裏
public class TestJson {
	public static void main(String[] args) throws JSONException {
		String str1 = "{name:'wangyafei',age:'20',sex:'man',fav:{1:'money',2:'money too'}}";
		JSONObject jsonObject = new JSONObject(str1);
		System.out.println(jsonObject.get("name"));
		System.out.println(jsonObject.get("age"));
		JSONObject fav = jsonObject.getJSONObject("fav");
		System.out.println(fav.get("1"));
		System.out.println(fav.get("2"));
		jsonObject.put("add", "mafang");
		System.out.println(jsonObject.toString());
		// -----------------------------------------------------------------------------------
		String str2 = "[{name:'wangyafei'},{age:'20',sex:'woman'},{sex:'man'},{fav:'money'}]";
		JSONArray array = new JSONArray(str2);
		System.out.println(array.length());
		System.out.println(array.getJSONObject(0).get("name"));
		System.out.println(array.getJSONObject(1).get("sex"));
		//for(int i = 0; i < array.length(); i++){
			//JSONObject object = array.getJSONObject(i);
			// 它是可以遍歷的
		//}

	}
}

第二種,用google的Gson包

解析

 import com.google.gson.stream.JsonReader;
String jsonData = "[{\"title\":\"西紅柿\",\"num\":50,\"unit\":\"公斤\"},{\"title\":\"洋蔥\",\"num\":50,\"unit\":\"公斤\"}]";
 JsonReader reader=new JsonReader(new StringReader(jsonData));
					 reader.beginArray();
					 while(reader.hasNext())
					 {
					 reader.beginObject();
					 while(reader.hasNext())
					 {
					 String name=reader.nextName();
					 if(name.equals("title"))
					 Log.e("title", reader.nextString()) ;
					 else if(name.equals("num"))
					 Log.e("num",reader.nextInt()+"");
					 else if(name.equals("unit"))
					 Log.e("unit", reader.nextString());
					 }
					 reader.endObject();
					 }
					 reader.endArray();
					 }

List轉Json

List<String> testList=new ArrayList<String>();
					testList.add("你好");
					testList.add("我好");
					testList.add("大家好");
					Gson gson=new Gson();
					String jsonStr=gson.toJson(testList);
System.out.prrintln(jsonStr);

輸出結果爲

12-10 06:27:41.484: I/System.out(482): ["你好","我好","大家好"]

List<Map<String,Object>>轉Json

List<Map<String,Object>> testList=new ArrayList<Map<String,Object>>();
					Map<String,Object> map=new HashMap<String, Object>();
					map.put("title", "豆子");
					map.put("num", 20);
					map.put("unit", "公斤");
					testList.add(map);
					map=new HashMap<String, Object>();
					map.put("title", "大米");
					map.put("num", 30);
					map.put("unit", "公斤");
					testList.add(map);
					map=new HashMap<String, Object>();
					map.put("title", "西紅柿");
					map.put("num", 40);
					map.put("unit", "公斤");
					testList.add(map);
					Gson gson=new Gson();
					String jsonStr=gson.toJson(testList);
System.out.println(jsonStr);

輸出結果爲:

12-10 06:44:10.764: I/System.out(568): [{"unit":"公斤","num":20,"title":"豆子"},{"unit":"公斤","num":30,"title":"大米"},{"unit":"公斤","num":40,"title":"西紅柿"}]