Changing IdentityUser's Id column's type to int - asp.net-core

Question

I am using .net core identity. When I create a new user in db, I can see that its ID column is GUID and it is string. I want to make it int so that User IDs can be 1,2,3 ...
How can I do that?

Answer 1

Usually we don't do that, It seems like it will be more complicated than simply adding a new id property with type int in your derived user class. But there still one way you can do it. Here's what plugging in guids instead of strings should look for example:
public class GuidRole : IdentityRole<Guid, GuidUserRole> {
public GuidRole() {
Id = Guid.NewGuid();
}
public GuidRole(string name) : this() { Name = name; }
}
public class GuidUserRole : IdentityUserRole<Guid> { }
public class GuidUserClaim : IdentityUserClaim<Guid> { }
public class GuidUserLogin : IdentityUserLogin<Guid> { }
public class GuidUser : IdentityUser<Guid, GuidUserLogin, GuidUserRole, GuidUserClaim> {
public GuidUser() {
Id = Guid.NewGuid();
}
public GuidUser(string name) : this() { UserName = name; }
}
private class GuidUserContext : IdentityDbContext<GuidUser, GuidRole, Guid, GuidUserLogin, GuidUserRole, GuidUserClaim> { }
private class GuidUserStore : UserStore<GuidUser, GuidRole, Guid, GuidUserLogin, GuidUserRole, GuidUserClaim> {
public GuidUserStore(DbContext context)
: base(context) {
}
}
private class GuidRoleStore : RoleStore<GuidRole, Guid, GuidUserRole> {
public GuidRoleStore(DbContext context)
: base(context) {
}
}
[TestMethod]
public async Task CustomUserGuidKeyTest() {
var manager = new UserManager<GuidUser, Guid>(new GuidUserStore(new GuidUserContext()));
GuidUser[] users = {
new GuidUser() { UserName = "test" },
new GuidUser() { UserName = "test1" },
new GuidUser() { UserName = "test2" },
new GuidUser() { UserName = "test3" }
};
foreach (var user in users) {
UnitTestHelper.IsSuccess(await manager.CreateAsync(user));
}
foreach (var user in users) {
var u = await manager.FindByIdAsync(user.Id);
Assert.IsNotNull(u);
Assert.AreEqual(u.UserName, user.UserName);
}
}