如何使用 netbeans 在 java 上验证从 jlabel 到 jtextfield 的值

Question

I have an auto generated numbers that i want the user to input in order to have access to the full function of the program, if the value from the label is the same with the value entered into the textbox, the functions should be enabeled else it should prompt out a JOptionPane that the value entered is not valid, if the value are input *3 it should exit the program.

Answer 1

Swing offers an InputVerifier for input verification. You could implement one and add it the JTextField . See InputVerifier docs . The textfield will get verified, as soon as another component requests the focus. You could enable/disable your components of choice in this verification-process. If this is not what you want, have a look at the KeyListener , you could also validate user input within KeyEvents .