标签:android
1.调用Environment.getExternalStorageState()判断手机上是否插入了SD卡,并且应用程序具有读写SD卡的权限。3.使用FileInputStream FileOutputStream FileReader FIleWriter 读写SD卡里的文件。
class Utils {
public void MyWrite(String data) throws Exception {
File sDfile = Environment.getExternalStorageDirectory();
File f = new File(sDfile, "demo.txt");
FileOutputStream fos = new FileOutputStream(f);
fos.write(data.getBytes());
fos.flush();
fos.close();
}
public String MyRead() throws Exception {
File sdFile = Environment.getExternalStorageDirectory();
File f = new File(sdFile, "demo.txt");
FileInputStream fis = new FileInputStream(f);
StringBuffer sb = new StringBuffer();
int len = 0;
while ((len = fis.read()) != -1){
sb.append((char)len);
}
return sb.toString();
}
}
public class MainActivity extends Activity {
private EditText write;
private Button saveButton, readButton;
private TextView show;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
show = (TextView) findViewById(R.id.show);
write = (EditText) findViewById(R.id.write);
saveButton = (Button) findViewById(R.id.save);
readButton = (Button) findViewById(R.id.read);
final Utils s = new Utils();
try {
show.setText(s.MyRead());
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
saveButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
try {
s.MyWrite(write.getText().toString());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
readButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
try {
show.setText(s.MyRead());
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
});
}
}
标签:android
原文地址:http://blog.csdn.net/u013476556/article/details/45539777