JSON(2)JSONObject解析Josn和创建Jsonf示例

1.解析Json

     /*
      * test.josn内容如下:
          {
             "languages":[
                  {"id":"1","name":"Java","ide":"Eclipse"}
                 ,{"id":"2","name":"Swift","ide":"Xcode"}
                 ,{"id":"3","name":"C#","ide":"Visual studio"}
             ]
             ,"cat":"it"
         }
      */
     void json_parser(){
         try {
             InputStreamReader isr = new InputStreamReader(getAssets().open("test.json"),"utf-8");
             BufferedReader br = new BufferedReader(isr);
             String line;
             StringBuilder builder = new StringBuilder();
             while ((line = br.readLine() ) != null) {
                 builder.append(line);
             }
             br.close();
             isr.close();

             JSONObject root = new JSONObject(builder.toString());

             /* 1.解析languages
                "languages":[
                  {"id":"1","name":"Java","ide":"Eclipse"}
                 ,{"id":"2","name":"Swift","ide":"Xcode"}
                 ,{"id":"3","name":"C#","ide":"Visual studio"}
                 ]
              */
             JSONArray languagesArray = root.getJSONArray("languages"); 

             output.setText("");
             for (int i = ; i < languagesArray.length(); i++) {
                 JSONObject lan  = languagesArray.getJSONObject(i);
                 output.append("\n");
                 output.append("\t id = " + lan.getInt("id"));
                 output.append("\t name = " + lan.getString("name"));
                 output.append("\t ide = " + lan.getString("ide"));
                 output.append("\n");
             }
             /*
              * 2.解析cat
              * "cat":"it"
              */
             output.append("\n\t cat = " + root.getString("cat"));

         } catch (IOException e) {
             output.append(e.getMessage());
             e.printStackTrace();
         } catch (JSONException e) {
             output.append(e.getMessage());
             e.printStackTrace();
         }
     }

2.创建Json

     void create_json(){
         JSONObject root = new JSONObject();
         try {
             /*
              * 1.创建 "cat"
              * "cat":"it"
              */
             root.put("cat", "it");

             /*
              * 2.创建 "languages"
              * "languages":[
                      {"id":"1","name":"Java","ide":"Eclipse"}
                     ,{"id":"2","name":"Swift","ide":"Xcode"}
                     ,{"id":"3","name":"C#","ide":"Visual studio"}
                 ]
              */
             JSONObject lan1 = new JSONObject();
             lan1.put("id", );
             lan1.put("name", "Java");
             lan1.put("ide", "Eclipse");

             JSONObject lan2 = new JSONObject();
             lan2.put("id", );
             lan2.put("name", "Swift");
             lan2.put("ide", "Xcode");

             JSONObject lan3 = new JSONObject();
             lan3.put("id", );
             lan3.put("name", "C#");
             lan3.put("ide", "Visual studio");

             JSONArray languagesArray = new JSONArray();
             languagesArray.put(lan1);
             languagesArray.put(lan2);
             languagesArray.put(lan3);

             root.put("languages", languagesArray);

             output.setText(root.toString());

         } catch (JSONException e) {
             e.printStackTrace();
         }
     }