为什么建立了键盘监听之后 按字母键键码值总是0 而方向键不好使

Question

键码值

Answer 1

这个可以
package com.tmzs.pc.jsoup;import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.io.FileNotFoundException;import javax.swing.JFrame;public class KeyBoardListener extends JFrame {
    
    public KeyBoardListener() throws FileNotFoundException {
        
        this.setTitle("监听键盘事件");
        this.setSize(800, 600);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setVisible(true);
        this.addKeyListener(new KeyAdapter()  {            @Override
            public void keyReleased(KeyEvent e) {
                char ch = e.getKeyChar();
                int num = e.getKeyCode() ;
                
                System.out.println("键盘="+ch+",代表数字="+num);
            }
            
        });
    }
    
    public static void main(String[] args) throws FileNotFoundException {
        new KeyBoardListener();
    }
}

Answer 2

public class KeyDemo extends JFrame{  this.setSize(400,400);
  this.setVisible(true);
 }
 public class MyListener extends KeyAdapter{
  public void keyPressed(KeyEvent arg0) {
   System.out.print(arg0.getKeyCode()); 
  }
 }
 public static void main(String[] aregs){
  new KeyDemo();
 }
}