I'm purposely not posting any code here as I'm really just looking for some guidance to the following problem:
I have created a three new fields in my AspNetUsers table - FirstName, LastName, and NickName. I also created a composite key using those three fields. When I try to create a new user that has all three of these fields the same, the application throws an error as expected when the unique rule is violated.
I would like it to simply post back to the Register User form indicating that the NickName must be changed to something else.
Do I need to implement a Custom User Store? Is there a simpler way?
Thank you for any suggestions.