kch.equals(\"\")
是
否
开始
public CSelect() {}
JLabel ltitle = new JLabel(\"课程号：\");JTextField tcno = new JTextField(8);JButton btnOK = new JButton(\"确定\");JPanel p = new JPanel();String kch = null;
public class CSelect extends JFrame implements ActionListener {}
kch = tcno.getText();
结束
public void actionPerformed(ActionEvent e) {}
