键盘事件处理程序

package _9;

import java.awt.BorderLayout;

import java.awt.event.KeyAdapter;

import java.awt.event.KeyEvent;

import javax.swing.JFrame;

import javax.swing.JLabel;

public class KeyEventDemo extends JFrame{

JLabel label = new JLabel("按下了按键:");

public KeyEventDemo() {

setSize(300, 300);

setLocation(400, 400);

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

this.addKeyListener(new KeyAdapter() {

public void keyPressed(KeyEvent event) {

switch (event.getKeyCode()) {

case KeyEvent.VK_UP:

label.setText("按下了按键:UP");

break;

case KeyEvent.VK_DOWN:

label.setText("按下了按键:DOWN");

break;

case KeyEvent.VK_LEFT:

label.setText("按下了按键:LEFT");

break;

case KeyEvent.VK_RIGHT:

label.setText("按下了按键:RIGHT");

break;

default:

label.setText("按下了按键:" + event.getKeyChar());

}

}

});

setLayout(new BorderLayout());

add(label, BorderLayout.CENTER);

}

public static void main(String[] args) {

KeyEventDemo frame = new KeyEventDemo();

frame.setVisible(true);

}

}