https://codingblast.com/connect4-live-game-signalr-blazor/ ‎- SignalR Connect4 Blazor

DbInitializer.cs

public interface IDbInitializer {
	Task Seed();
}

public class DbInitializer: IDbInitializer {
	private readonly ILogger < DbInitializer > _logger;
	private readonly UserManager < IdentityUser > _userManager;
	private readonly ApplicationDbContext _dbContext;
	private readonly IWebHostEnvironment _environment;

	public DbInitializer(ILogger < DbInitializer > logger, UserManager < IdentityUser > userManager, ApplicationDbContext dbContext, IWebHostEnvironment environment) {
		_logger = logger;

		_userManager = userManager;
		_dbContext = dbContext;
		_environment = environment;
	}

	public async Task Seed() {
		if (!_environment.IsDevelopment()) {
			return;
		}

		_logger.LogInformation("Migrating DB");
		await _dbContext.Database.MigrateAsync();
		_logger.LogInformation("Migrated DB");

		_logger.LogInformation("Seeding Users");
		await SeedUsers();
		_logger.LogInformation("Seeded Users");
	}

	private async Task < List < IdentityUser >> SeedUsers() {
		if (await _dbContext.Users.CountAsync() >= 2) {
			return null;
		}

		var user1 = await CreateUser("[email protected]", "Test1234!!!");
		var user2 = await CreateUser("[email protected]", "Test1234!!!");

		return new List < IdentityUser > {
			user1,
			user2
		};
	}

	private async Task < IdentityUser > CreateUser(string userName, string password) {
		var user = new IdentityUser {
			UserName = userName,
			Email = userName
		};

		var result = await _userManager.CreateAsync(user, password);
		if (result.Succeeded) {
			var code = await _userManager.GenerateEmailConfirmationTokenAsync(user);
			await _userManager.ConfirmEmailAsync(user, code);

			return user;
		}
		else {
			throw new ApplicationException("Couldn't create user");
		}
	}
}