在Android手机中从SD卡删除文件

Question

I want to delete a file named "playerdata.txt" on an SD card. The following code is not working

{
    File file = new File("/sdcard/GameHacker/playerdata.txt");
    file.delete();
}

My problem is I want to copy "playerdata.txt" to that folder called GameHacker and I use this code

Context Context = getApplicationContext();

String DestinationFile = "/sdcard/GameHacker/playerdata.txt";
if (!new File(DestinationFile).exists()) {
  try {
    CopyFromAssetsToStorage(Context, "playerdata", DestinationFile);
  } catch (IOException e) {
    e.printStackTrace();
  }
}
}

private void CopyFromAssetsToStorage(Context Context, String SourceFile, String DestinationFile) throws IOException {
  InputStream IS = Context.getAssets().open(SourceFile);
  OutputStream OS = new FileOutputStream(DestinationFile);
  CopyStream(IS, OS);
  OS.flush();
  OS.close();
  IS.close();
}
private void CopyStream(InputStream Input, OutputStream Output) throws IOException {
  byte[] buffer = new byte[5120];
  int length = Input.read(buffer);
  while (length > 0) {
    Output.write(buffer, 0, length);
    length = Input.read(buffer);

  }

}

and it works fine but the second time it doesn't replace it and I want to first delete that and then copy and I add the

> <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>

to manifest

Answer 1

Ty adding

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>

in AndroidManifest.xml file

Answer 2

There may be many reason for file not being deleted. One of them is that your app dont have write permission for sd card. Try to include that permission android:name="android.permission.WRITE_EXTERNAL_STORAGE