Question

I use checkbox in WPF window. I use some logic in unchecked event of checkbox. And I want to cancel uncheck if need it in the body of this event. How can I do this?

    private void chApprove_Checked(object sender, RoutedEventArgs e)
    {
        btnAddDepartment.IsEnabled = true;
        brnRemoveDepartment.IsEnabled = true;
    }

    private void chApprove_Unchecked(object sender, RoutedEventArgs e)
    {
        if (lbSource.Count == 0)
        {
            btnAddDepartment.IsEnabled = false;
            brnRemoveDepartment.IsEnabled = false;
        }
        else
        {
            MessageBox.Show("Staff already in use! Release it first from dependecies!");
            CheckBox myCheckBox = e.Source as CheckBox;
            myCheckBox.IsChecked = true;


        }
    }

Impossible to cancel uncheck !!!

Answer 1

You could do this easily with an attached behavior (rather than using code behind), you can take a look at this answer if you need a sample of how to structure one (it’s only a few lines of code).

My spider-sense is telling me this isn’t a very good idea though – I can’t imagine a way to “justify” rechecking a checkbox that a user has clicked, it just strikes me as very jarring. Can you not either bind the enabled state of the checkbox to a property on your ViewModel or, if you have an ICommand bound to it, use the CanExecute delegate to enable/disable it based on the same logic?