读写内部存储的文件数据

<EditText

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:id="@+id/et"

android:hint="在这里输入内容" />

<Button

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:text="保存数据"

android:id="@+id/btnWrite" />

<Button

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:text="读取数据"

android:id="@+id/btnRead" />

<TextView

android:layout_width="fill_parent"

android:layout_height="wrap_content"

android:text="New Text"

android:id="@+id/tvShow" />

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

private TextView show;

private EditText et;

private String fileName="test";

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

show= (TextView) findViewById(R.id.tvShow);

et= (EditText) findViewById(R.id.et);

findViewById(R.id.btnRead).setOnClickListener(this);

findViewById(R.id.btnWrite).setOnClickListener(this);

}

@Override

public void onClick(View v) {

switch (v.getId()){

case R.id.btnRead:

try {

FileInputStream fis= openFileInput(fileName);

InputStreamReader is=new InputStreamReader(fis,"UTF-8");

char input[]=new char[fis.available()];

is.read(input);

is.close();

fis.close();

String readed=new String(input);

show.setText(readed);

System.out.println("读取数据成功");

} catch (FileNotFoundException e) {

e.printStackTrace();

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

break;

case R.id.btnWrite:

try {

FileOutputStream fos=openFileOutput(fileName, Context.MODE_PRIVATE);  //应用程序输入写入内部存储

OutputStreamWriter osw=new OutputStreamWriter(fos,"UTF-8");

osw.write(et.getText().toString());

osw.flush();

fos.flush();

osw.close();

fos.close();

Toast.makeText(MainActivity.this, "写入内部数据完成", Toast.LENGTH_LONG);

System.out.println("写入内部数据完成");

} catch (FileNotFoundException e) {

e.printStackTrace();

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

break;

}

}

}