Android FileInputStream read（）txt文件转换为String

Question

有专家可以帮助我吗？在我的Android主要活动中，我试图将字符串保存到文件中，然后如果用户之前对其进行设置，则将其检索。无法找到与我正在做的事情相近的例子。我将不胜感激任何帮助！这是我崩溃的测试用例：

String testString = "WORKS";
String readString;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    FileOutputStream fos;

    try {
        fos = openFileOutput("test.txt", Context.MODE_PRIVATE);
        fos.write(testString.getBytes());
        fos.close();
    } catch (FileNotFoundException e) {
        e.printStackTrace();

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

    }

    File file = getBaseContext().getFileStreamPath("test.txt");

    if (file.exists()) {

        FileInputStream fis;

        try {
            fis = openFileInput("test.txt");
            fis.read(readString.getBytes());
            fis.close();

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

        }

        txtDate.setText(String.valueOf(readString));

       } else {
                     // more code
       }
     }
 }

Answer 1

要读取文件，请尝试以下操作：

FileInputStream fis;
fis = openFileInput("test.txt");
StringBuffer fileContent = new StringBuffer("");

byte[] buffer = new byte[1024];

while ((n = fis.read(buffer)) != -1) 
{ 
  fileContent.append(new String(buffer, 0, n)); 
}