扩展UserManager以包括按自定义字段ASP.net核心进行搜索

public class CustomUserManager<TUser> : UserManager<TUser> where TUser : class
{
    public CustomUserManager(IUserStore<TUser> store, IOptions<IdentityOptions> optionsAccessor, 
        IPasswordHasher<TUser> passwordHasher, IEnumerable<IUserValidator<TUser>> userValidators, 
        IEnumerable<IPasswordValidator<TUser>> passwordValidators, ILookupNormalizer keyNormalizer, 
        IdentityErrorDescriber errors, IServiceProvider services, ILogger<UserManager<TUser>> logger) 
        : base(store, optionsAccessor, passwordHasher, userValidators, passwordValidators, keyNormalizer, errors, services, logger)
    {
    }

    // 添加自定义的搜索方法
    public async Task<List<TUser>> SearchByCustomFieldAsync(string fieldName, string value)
    {
        // 根据自定义字段进行搜索
        var users = await Users.Where(u => EF.Property<string>(u, fieldName) == value).ToListAsync();
        return users;
    }
}

services.AddDefaultIdentity<ApplicationUser>(options => options.SignIn.RequireConfirmedAccount = true)
    .AddEntityFrameworkStores<ApplicationDbContext>()
    .AddUserManager<CustomUserManager<ApplicationUser>>();

private readonly CustomUserManager<ApplicationUser> _userManager;

public YourController(CustomUserManager<ApplicationUser> userManager)
{
    _userManager = userManager;
}

public async Task<IActionResult> Search(string fieldName, string value)
{
    var users = await _userManager.SearchByCustomFieldAsync(fieldName, value);
    // 处理搜索结果
    return View(users);
}