How to skip Validating after clicking on a Form's Cancel button

Question

I use C#. I have a Windows Form with an edit box and a Cancel button. The edit box has code in validating event. The code is executed every time the edit box loses focus. When I click on the Cancel button I just want to close the form. I don't want any validation for the edit box to be executed. How can this be accomplished?

Here is an important detail: if the validation fails, then

            e.Cancel = true;

prevents from leaving the control.

But when a user clicks Cancel button, then the form should be closed no matter what. how can this be implemented?

Answer 1

If the validation occurs when the edit box loses focus, nothing about the the cancel button is going to stop that from happening.

However, if the failing validation is preventing the cancel button from doing its thing, set the CausesValidation property of the button to false.

Reference: Button.CausesValidation property

Answer 2

Obviously CausesValidation property of the button has to be set to false and then the validating event will never happen on its click. But this can fail if the parent control of the button has its CausesValidation Property set to true. Most of the time developers misses/forgets to change the CausesValidation property of the container control (like the panel control). Set that also to False. And that should do the trick.

Answer 3

I was having problems getting my form to close, since the validation of certain controls was stopping it. I had set the control.CausesValidation = false for the cancel button and all the parents of the cancel button. But still was having problems.

It seemed that if the user was in the middle of editing a field that was using validation and just decided to give up (leaving the field with an invalid input), the cancel button event was being fired but the window would not close down.

This was fixed by the following in the cancel button click event:

private void btnCancel_Click(object sender, EventArgs e)
{
    // Stop the validation of any controls so the form can close.
    AutoValidate = AutoValidate.Disable;
    Close();
}

Answer 4

Set the CausesValidation property of the Cancel button to false.

Answer 5

Set the CausesValidation property to false.

Answer 6

None of these answers quite did the job, but the last answer from this thread does. Basically, you need to:

1. Insure that the Cancel button (if any) has .CausesValidation set to false

2. Override this virtual method.

   protected override bool ProcessDialogKey(Keys keyData) {
       if (keyData == Keys.Escape) {
           this.AutoValidate = AutoValidate.Disable;
           CancelButton.PerformClick();
           this.AutoValidate = AutoValidate.Inherit;
           return true;
       }
       return base.ProcessDialogKey(keyData);
   }
   

I didn't really answer this, just pointing to the two guys who actually did.

Answer 7

Setting CausesValidation to false is the key, however this alone is not enough. If the buttons parent has CausesValidation set to true, the validating event will still get called. In one of my cases I had a cancel button on a panel on a form, so I had to set CausesValidation = false on the panel as well as the form. In the end I did this programatically as it was simpler than going through all the forms...

Control control = cancelButton;

while(control != null)
{
   control.CausesValidation = false;
   control = control.Parent;
}

Answer 8

In my case, in the form I set the property AutoValidate to EnableAllowFocusChange

Answer 9

By using Visual Studio wizard you can do it like that:

Answer 10

Judicious use of the Control.CausesValidation property will help you achieve what you want.

Answer 11

Just above the validation code on the edit box add:

if (btnCancel.focused)
  {
     return;
  }

That should do it.

Answer 12

In complement of the answer of Daniel Schaffer: if the validation occurs when the edit box loses focus, you can forbid the button to activate to bypass local validation and exit anyway.

public class UnselectableButton : Button
{
    public UnselectableButton()
    {
        this.SetStyle(ControlStyles.Selectable, false);
    }
}

or if you use DevExpress:

this.simpleButtonCancel.AllowFocus = false;

Note that doing so will change the keyboard experience: the tab will focus anymore on the cancel button.