其實就是用java的IO流去讀取檔案

public static String ReadTxtFile(String strFilePath) {

    String path = strFilePath;

    String gpioValue = "";

    //開啟檔案
File file = new File(path);

    //如果path是傳遞過來的引數，可以做一個非目錄的判斷
if (file.isDirectory()) {

        Log.d(TAG, "這個目錄不存在");

    } else {

        try {

            InputStream instream = new 
 
FileInputStream(file);

            if (instream != null)

            {

                InputStreamReader inputreader = new InputStreamReader(instream);

                BufferedReader buffreader = new BufferedReader(inputreader);

                String line;
                //分行讀取
while ((line = buffreader.readLine()) != null
 
) {

                    gpioValue = line;

                }
                Log.i("gpioValue-----------", gpioValue + "==============");

                instream.close();

            }

        } catch (java.io.FileNotFoundException e) {

            Log.d(TAG, "檔案目錄異常或不存在");

        } catch (IOException e) {

            Log.d
 
(TAG, e.getMessage());

        }
    }

    return gpioValue;
}