using System;

using Microsoft.AspNetCore.Identity;

public class Program

{

    public static void Main()

    {

        IPasswordHasher<AppUser> hash = new PasswordHasher<AppUser>();

        AppUser user = new AppUser

        {

            Username = "admin",

            PasswordHash = ""

        };

        user.PasswordHash = hash.HashPassword(user, "admin");

        var result = hash.VerifyHashedPassword(user, "AQAAAAIAAYagAAAAEL4t8hKbhDtdvH9Au/z5ZVRn9oTq1EdUyMZaXDIxR1qbfiohWMpCSO3Ac8VzNRsmEg==", "admin");

        Console.WriteLine(user.PasswordHash);

        Console.WriteLine(result is PasswordVerificationResult.Success);

    }

}

​

public class AppUser

{

    public string Username { get; set; }

    public string PasswordHash { get; set; }

}