在Android中对文件的读写操作

梦里梦外; 2022-07-18 05:28 210阅读 0赞

package com.example.filedemo2;
    
    import java.io.ByteArrayOutputStream;
    import java.io.FileInputStream;
    import java.io.FileNotFoundException;
    import java.io.FileOutputStream;
    import java.io.IOException;
    
    import org.w3c.dom.Text;
    
    import android.R.integer;
    import android.app.Activity;
    import android.content.SharedPreferences.Editor;
    import android.os.Bundle;
    import android.view.Menu;
    import android.view.MenuItem;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.EditText;
    import android.widget.TextView;
    import android.widget.Toast;
    
    
    public class MainActivity extends Activity {
    	EditText editText;
    	Button button;
    	TextView textView;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            editText=(EditText) findViewById(R.id.editText1);
            button=(Button) findViewById(R.id.button1);
            textView=(TextView) findViewById(R.id.textView1);
            button.setOnClickListener(new OnClickListener() {
    			
    			@Override
    			public void onClick(View v) {
    				// TODO Auto-generated method stub
    				WriteFile(editText.getText().toString());
    				//Toast.makeText(MainActivity.this,ReadFile(),Toast.LENGTH_SHORT).show();
    				textView.setText(ReadFile());
    			}
    		});
        }
        public void WriteFile(String content){
        	try {
    			FileOutputStream fos=openFileOutput("a.text",MODE_PRIVATE);
    			fos.write(content.getBytes());
    			fos.close();
    		} catch (FileNotFoundException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} catch (IOException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
        }
        public String ReadFile(){
        	String content=null;
        	try {
    			FileInputStream fis=openFileInput("a.text");
    			ByteArrayOutputStream baos=new ByteArrayOutputStream();
    			byte[] buffer=new byte[1024];
    			int len=0;
    			while((len=fis.read(buffer))!=-1){
    				baos.write(buffer,0, len);
    			}
    			content=baos.toString();
    			fis.close();
    			baos.close();
    		} catch (FileNotFoundException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} catch (IOException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
        	return content;
        }
    }