关于android写入SD卡数据的学习代码

String path = "data/data/com.example.qqlogin/login.txt";
FileOutputStream fos = new FileOutputStream(path);
String data = number + "##" + password;
fos.write(data.getBytes());
fos.flush();
fos.close();  
或者
public class MainActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);

		// /data/data/包名/files/aa.txt
		// openFileOutput("aa.txt", Context.mode)
		//私有文件
		writeToLocal("private.txt",Context.MODE_PRIVATE);
		//可读文件
		writeToLocal("readable.txt", Context.MODE_WORLD_READABLE);
		//可写文件
		writeToLocal("writeable.txt", Context.MODE_WORLD_WRITEABLE);
		//可读可写
		writeToLocal("readable_writeable", Context.MODE_WORLD_READABLE + Context.MODE_WORLD_WRITEABLE);
	}
	
	private void writeToLocal(String fileName,int mode){
		
		try {
			FileOutputStream fos  = openFileOutput(fileName, mode);
			fos.write(("第一个程序写的数据："+fileName).getBytes());
			fos.flush();
			fos.close();
		} catch (Exception e) {
			// TODO 自动生成的 catch 块
			e.printStackTrace();
		}
		
	}
}