How do I get a TextBox to only accept numeric input in WPF?

Question

I\'m looking to accept digits and the decimal point, but no sign.

I\'ve looked at samples using the NumericUpDown control for Windows Forms, and this sample of a Num

Answer 1

e.Handled = (int)e.Key >= 43 || (int)e.Key <= 34;

in preview keydown event of textbox.