java - 从 JSON 中提取

Question

"biodata": {
    "Ruby": {
      "Expertise": "web development",
      "EXperience": "5 years"
    },
    "Dylon": {
      "Expertise": "Java",
      "EXperience": "2 years"
    }
 }

我有上面的 JSONObject 。我正试图在这里取一些 key 。

1. 我正在寻找名称键，即 Ruby、Dylon 等。
2. 然后我尝试获取“Experience”键值。

所需输出:

名称= ruby
经验 = 5 年

我的代码:

JSONParser parser = new JSONParser();

Object obj = parser.parse(new FileReader("path to JSON file"));

JSONObject jsonobj = (JSONObject) obj;

String statistics = jsonobj.getString("biodata"); //The method getString(String) is undefined for the type JSONObject

for (Iterator key = jsonobj.keys(); itr.hasNext();) {//The method keys() is undefined for the type JSONObject //itr cannot be resolved
     JSONObject name = jsonobj.get(key.next()); //Type mismatch: cannot convert from Object to JSONObject		
     String key = key.next();//The method next() is undefined for the type String
     JSONObject name = jsonobj.get(key); //Type mismatch: cannot convert from Object to JSONObject
     Log.d("data", "key="+key+ " and value="+jsonobj.toString()); //Log cannot be resolved		
}

我已经在代码注释中提到了错误。

Answer 1

您的 json 无效。

你应该改成这个。

{ 
 "biodata": {
    "Ruby": {
      "Expertise": "web development",
      "EXperience": "5 years"
    },
    "Dylon": {
      "Expertise": "Java",
      "EXperience": "2 years"
    }
 }
}

试试这个。

private void jsonParse() {
    try {
        // use jsonobject to parse json with 
        JSONParser parser = new JSONParser();

        Object obj = parser.parse(new FileReader("path to JSON file"));

        JSONObject jsonObject = (JSONObject) obj;

        // get jsonobject by biodata tag
        JSONObject biodata = jsonObject.getJSONObject("biodata");
        // use Iterator to get name 
        Iterator<String> names = biodata.keys();
        // use while loop
        while (names.hasNext()) {
            // get name 
            String name = names.next().toString();
            Log.d("data", "name=" + name);
            // get jsonobject by name tag 
            JSONObject nameJsonObject = biodata.getJSONObject(name);
            // get string 
            String Expertise = nameJsonObject.getString("Expertise");
            String EXperience = nameJsonObject.getString("EXperience");
            Log.d("data", "Experience =" + EXperience);
        }
    } catch (JSONException e) {
        e.printStackTrace();
    }
}