use javax.swing.JFormattedTextField or DocumentListener
import java.awt.Toolkit; import java.awt.event.KeyEvent; import java.awt.event.KeyAdapter; //this class for monitoring keyTyped public class KeyAction extends KeyAdapter{
public void keyTyped(KeyEvent e){ char ch=e.getKeyChar(); String detectStr;
//only 0 to 9 backspace or delete key character can be input if(ch>0x2f&&ch<0x3a||ch==0x08||ch==0x10||ch==0x2e){
}else{ Toolkit.getDefaultToolkit().beep(); e.consume();//for consuming the listener }
import java.awt.event.KeyEvent;
import java.awt.event.KeyAdapter;
//this class for monitoring keyTyped
public class KeyAction extends KeyAdapter{
public void keyTyped(KeyEvent e){
char ch=e.getKeyChar();
String detectStr;
//only 0 to 9 backspace or delete key character can be input
if(ch>0x2f&&ch<0x3a||ch==0x08||ch==0x10||ch==0x2e){
}else{
Toolkit.getDefaultToolkit().beep();
e.consume();//for consuming the listener
}
}//end of keyTyped
}//end of class
不过,根据经验,这个Listener应当是最后被add的