// 上下文對象
private Context context;
public FileService(Context context)
{
super();
this.context = context;
}
// 保存文件方法
public void save(String filename, String fileContent) throws Exception
{
FileOutputStream fos = context.openFileOutput(filename, context.MODE_PRIVATE);
fos.write(fileContent.getBytes("UTF-8"));
fos.close();
}

FileOutputStream outStream = this.openFileOutput("xy.txt",Context.MODE_WORLD_READABLE+Context.MODE_WORLD_WRITEABLE);

FileOutputStream outStream = this.openFileOutput("xy.txt",Context.MODE_APPEND+Context.MODE_WORLD_READABLE+Context.MODE_WORLD_WRITEABLE);