java - 如何将 "Data.Json"文件从 Assets 保存到内部存储，然后将其用于读/写

Question

目前，我正在从 assets 的 Json 文件“Data.json”中获取包裹详细信息(在线分钟数、离线分钟数等)，但我知道我们无法更改来自 Assets 的值(value)。所以我的问题是如何将 Data.json 复制到内部存储，然后加载它以进行读/写。

我正在使用它从 Assets 加载 Data.Json

    public String loadJSONFromAsset() {
    String json = null;
    try {
        InputStream is = getAssets().open("Data.json");
        int size = is.available();
        byte[] buffer = new byte[size];
        is.read(buffer);
        is.close();
        json = new String(buffer, "UTF-8");
        Toast.makeText(jazz_sim_lagao_offer_details.this, "JSON Loaded", Toast.LENGTH_SHORT).show();
    } catch (IOException ex) {
        ex.printStackTrace();
        return null;
    }
    return json;
}

并使用此代码更新数据

    private void UpdateData() {
    JSONObject JSONobj = null;
    try {
        loadJSONFromAsset();
        //get JSONObject from JSON file
        JSONobj = new JSONObject(loadJSONFromAsset());
        //fetch JSONObject named
        JSONObject Jazz_SimLagaoOffer = JSONobj.getJSONObject("packages").getJSONObject("jazz_packages").getJSONObject("call_packages").getJSONObject("sim_lagao_offer");



        String Jazz_SimLagaoOffer_ONNET = Jazz_SimLagaoOffer.getString("onnet");
        Jazz_SimLagaoOffer_OnNet_TextView.setText(Jazz_SimLagaoOffer_ONNET);

        String Jazz_SimLagaoOffer_OFFNET = Jazz_SimLagaoOffer.getString("offnet");
        Jazz_SimLagaoOffer_OffNet_TextView.setText(Jazz_SimLagaoOffer_OFFNET);

        String Jazz_SimLagaoOffer_MBs = Jazz_SimLagaoOffer.getString("mbs");
        Jazz_SimLagaoOffer_Mb_TextView.setText(Jazz_SimLagaoOffer_MBs);

        String Jazz_SimLagaoOffer_SMS = Jazz_SimLagaoOffer.getString("sms");
        Jazz_SimLagaoOffer_Sms_TextView.setText(Jazz_SimLagaoOffer_SMS);


        String Jazz_SimLagaoOffer_SUBCODE = Jazz_SimLagaoOffer.getString("sub_code");
        Jazz_SimLagaoOffer_Sub_Code_TextView.setText(Jazz_SimLagaoOffer_SUBCODE);


        String Jazz_SimLagaoOffer_CHECKCODE = Jazz_SimLagaoOffer.getString("check_code");
        Jazz_SimLagaoOffer_Check_Code_TextView.setText(Jazz_SimLagaoOffer_CHECKCODE);

        String Jazz_SimLagaoOffer_UNSUBCODE = Jazz_SimLagaoOffer.getString("unsub_code");
        Jazz_SimLagaoOffer_Unsub_Code_TextView.setText(Jazz_SimLagaoOffer_UNSUBCODE);

        Jazz_SimLagaoOffer_Charges = Jazz_SimLagaoOffer.getString("charges");

    } catch (JSONException e) {
        e.printStackTrace();
        Toast.makeText(getBaseContext(), JSONobj + "", Toast.LENGTH_SHORT).show();
    }

}

如何获取Json对象？

这是我的Data.Json

{
  "packages" : {
    "jazz_packages" : {
      "call_packages" : {
        "sim_lagao_offer" : {
          "charges" : "0.01",
          "check_code" : "*551*2#",
          "mbs" : "1500",
          "offnet" : "5000",
          "onnet" : "3000",
          "sms" : "3000",
          "sub_code" : "*551#",
          "unsub_code" : "*551*3#"
        }
      }
    }
  }
}

Answer 1

试试这个

private void CopyAssets() {
    AssetManager assetManager = getAssets();
    String[] files = null;



        System.out.println("File name => "+filename);
        InputStream in = null;
        OutputStream out = null;
        try {
            in = assetManager.open(YOUR_ASSETS_FILE);   // if files resides inside the "Files" directory itself
            out = new FileOutputStream(STORAGE_PATH).toString() +"/" + filename);
            copyFile(in, out);
            in.close();
            in = null;
            out.flush();
            out.close();
            out = null;
        } catch(Exception e) {
           e.printStackTrace();
        }

}
private void copyFile(InputStream in, OutputStream out) throws IOException {
    byte[] buffer = new byte[1024];
    int read;
    while((read = in.read(buffer)) != -1){
        out.write(buffer, 0, read);
    }
}

使用下面的代码从存储中读取

    String jsongString = readFromFile();
    JSONObject mainJsonObject = new JSONObject(jsongString);
    JSONObject Jazz_SimLagaoOffer = mainJsonObject.getJSONObject("packages").getJSONObject("jazz_packages").getJSONObject("call_packages").getJSONObject("sim_lagao_offer");

使用以下方法从内部存储文件读取数据并以字符串形式返回。

private String readFromFile() {

String ret = "";
InputStream inputStream = null;
try {
    inputStream = openFileInput("names.json");

    if ( inputStream != null ) {
        InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
        String receiveString = "";
        StringBuilder stringBuilder = new StringBuilder();

        while ( (receiveString = bufferedReader.readLine()) != null ) {
            stringBuilder.append(receiveString);
        }

        ret = stringBuilder.toString();
    }
}
catch (FileNotFoundException e) {
    Log.e("login activity", "File not found: " + e.toString());
} catch (IOException e) {
    Log.e("login activity", "Can not read file: " + e.toString());
}
finally {
  try {
     inputStream.close();
  } catch (IOException e) {
    e.printStackTrace();
  }
}

return ret;

}

希望这能成功:)