java - "A JSONArray text must start with ' [' at character 1 of null"

Question

只是想知道这个错误可能意味着什么？我从下面的代码中得到它..

 try{
    JSONArray jArray = new JSONArray(result);
    for(int i=0;i<jArray.length();i++){
            JSONObject json_data = jArray.getJSONObject(i);
            Log.i("log_tag","id: "+json_data.getInt("id")+
                    ", name: "+json_data.getString("name")+
                    ", sex: "+json_data.getInt("sex")+
                    ", birthyear: "+json_data.getInt("birthyear")
            );
    }
}
}catch(JSONException e){
    Log.e("log_tag", "Error parsing data "+e.toString());
}

Answer 1

结果显然是空的。或者它根本不以 [ 开头。在调用 JSONArray 之前打印出来看看。

另请查看JSONArray source 。它需要 JavaScript 数组语法，例如:

['这个', '是', '数组', '语法']