10.30keyeventdemo.java

JAVA程序设计的源代码

import java.awt.Frame;
import java.awt.TextArea;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
public class KeyEventDemo implements KeyListener {
public void keyTyped(KeyEvent arg0){    //键盘处理函数
System.out.println("<--处理keyTyped事件-->");
}
public void keyPressed(KeyEvent arg0){    //键盘按下事件处理函数
System.out.println( "<--处理keyPressed事件-- >");
}
public void keyReleased(KeyEvent arg0){     //键盘按下事件处理函数
System.out.println( "<--处理keyReleased事件-->");
TextArea area = (TextArea)arg0.getSource();
String s = area.getText().toUpperCase();   //将文本框中字母转为大写
area.setText (" ");   
area.append(s);    //写入转为大写的文本
}
public static void main(String []args) {
Frame frame = new Frame ("容器");
frame.setLocation(200, 200);
frame.setSize(300,300);
TextArea area=new TextArea();
area.addKeyListener(new KeyEventDemo());    //设置事件监听
//将TextArea组件添加到frame组件中
frame.add(area);
frame.setVisible(true);
}
}