This demo project shows how to extend the IdentityUser class by adding two custom properties:
- A scalar property 
FiscalCodeof type string; - A navigation property 
Addressesto a list of custom entities of typeUserAddress. 
The UI provided by ASP.NET Core Identity has been customized to let the user set values for both these new properties.
New values have been included in the JSON file the user can download from the "Personal Data" page, as per the GDPR regulation. Here's a sample of the JSON file.
{
 "FiscalCode":null,
 "Addresses":[
   {"Address":"Via Fermi 16, 62024 Matelica MC"},
   {"Address":"Corso Europa 118, 62032 Camerino MC"}
 ],
 "Id":"8419af3a-70ed-46bc-b276-762c8771eeb6",
 "UserName":"demo@example.com",
 "Email":"demo@example.com",
 "EmailConfirmed":"False",
 "PhoneNumber":null,
 "PhoneNumberConfirmed":"False",
 "TwoFactorEnabled":"False"
}
