I have two dates, (Activation date and Expiry date) on my WPF form.
Now validation I have to check is that Activation Date should be less
then Expiry date.
Now How can I build a validator to achive this task?
What I have done on my form is I have created Error Template for
controls that i use in app.
I can check this validation by code also
but in this case my error template is not shown.