C# error messages for incorrect input value (regex) and empty textboxes

Question

Hey there, I have a question about Regex and error checking for empty text boxes.

I have a windows form application which has a name textbox, phone number textbox, and email textbox. They all have regex assigned, basically, when the user clicks the submit button, is there a way i can display a messagebox which gives the user info on which textbox has failed? Ie if they enter letters into the phone number text box, a message box would pop up and say something like "Please no letters, only numbers" etc etc.

Obviously I could use a general messagebox, but that seems quite unusable, as it doesn't highlight the errors ,and it might be difficult to pinpoint such errors in some circumstances.

Thanks in advance,
Ari