按键监听

import java.awt.*;import java.awt.event.*;import java.applet.*;public class A extends Applet implements ActionListener{String msg="";Label lb=new Label("        请问母亲节在那个月份？");TextField tf=new TextField(30);public void init(){add(lb);Button a=new Button("1");Button b=new Button("3");Button c=new Button("5");Button d=new Button("7");add(a);add(b);add(c);add(d);a.addActionListener(this);b.addActionListener(this);c.addActionListener(this);d.addActionListener(this);}public void actionPerformed(ActionEvent e){String str=e.getActionCommand();if (str=="5"){msg="你是个好孩子";}else{msg="你是个不孝子";}repaint();}public void paint(Graphics g){g.drawString(msg,6,100);}}