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Java

Posted by Khaleel Hamid
Khaleel Hamid
5,258 Points

How to validate a textbox to accept numbers only

How can I validate a textbox to accept numbers only?

private class ButtonHandler implements ActionListener
{
     @Override
     public void actionPerformed(ActionEvent ae) 
     {
          JButton btn = (JButton)ae.getSource();
          if (btn == btnGenerate) 
          {
              if (txtRow.getText().equals("") || txtCol.getText().equals("")) 
              {
                  JOptionPane.showMessageDialog(null, "Please enter number");
              }
           }
}

I have this so far, but it allows characters, but all I want is numbers.

2 Answers

Ken Alger
STAFF
Ken Alger
Treehouse Teacher
Ken Alger
Ken Alger
Treehouse Teacher

Khaleel;

I would look at the JFormattedTextField options.

Ken

Khaleel Hamid
Khaleel Hamid
5,258 Points

Thanks I'll have a look into that.

Craig Dennis
STAFF
Craig Dennis
Treehouse Teacher
Craig Dennis
Craig Dennis
Treehouse Teacher

Regular expressions might make your head spin a bit, but they are great for things like this.