I have six textboxes in my WPF app, and I want to check if every single one of them is filled (that means the textboxes contains at least one letter, number, etc. (datatype doesn't matter!))
When not, I want to pop up Messagebox to inform the user to check them once again (that's just for context, I know how to do this specific thing). How do I check that? Everywhere I've searched, they somehow did it but in Windows Forms, which is not what I need, obviously.