How do I make a textbox visible and hidden with a checkbox?

Question

So I am trying to make my textbox invisible when a checkbox is not checked. Everything works fine untill I check the box and then uncheck it again. The textbox will stay vis

Answer 1

when CheckBox goes to unchecked state, Unchecked event fires (simmetric to Checked). Add event handler to both of them.

private void chbon_Checked_1(object sender, RoutedEventArgs e)
{
     txtshow.Visibility = cchbon.IsChecked ? Visibility.Visible : Visibility.Hidden;
}

It is common to use binding to boolean property to set Visibility of some element. There is a BooleanToVisibilityConverter in .NET, which returns Visible for true, and Collapsed for false. Collapsed is different from Hidden: Hidden element stil claims the space on the screen as if it was Visible.

There is a way to achieve everything in XAML using a Trigger: