如何对asp.net核心身份单独使用外部身份验证

services.AddAuthentication().AddGoogle(options =>
{
    options.ClientId = "your-client-id";
    options.ClientSecret = "your-client-secret";
});

[AllowAnonymous]
public IActionResult ExternalLogin(string provider, string returnUrl = null)
{
    var redirectUrl = Url.Action("ExternalLoginCallback", "Account", new { ReturnUrl = returnUrl });
    var properties = _signInManager.ConfigureExternalAuthenticationProperties(provider, redirectUrl);
    return new ChallengeResult(provider, properties);
}

[AllowAnonymous]
public async Task<IActionResult> ExternalLoginCallback(string returnUrl = null, string remoteError = null)
{
    if (remoteError != null)
    {
        // 处理外部身份验证错误
        return RedirectToAction("Login");
    }
    var info = await _signInManager.GetExternalLoginInfoAsync();
    if (info == null)
    {
        // 处理外部身份验证信息获取失败
        return RedirectToAction("Login");
    }
    var result = await _signInManager.ExternalLoginSignInAsync(info.LoginProvider, info.ProviderKey, isPersistent: false, bypassTwoFactor: true);
    if (result.Succeeded)
    {
        // 处理外部身份验证成功
        return RedirectToLocal(returnUrl);
    }
    if (result.IsLockedOut)
    {
        // 处理用户账户锁定
        return RedirectToAction("Lockout");
    }
    else
    {
        // 处理新用户注册
        ViewData["ReturnUrl"] = returnUrl;
        ViewData["LoginProvider"] = info.LoginProvider;
        return View("ExternalLoginConfirmation", new ExternalLoginConfirmationViewModel { Email = info.Principal.FindFirstValue(ClaimTypes.Email) });
    }
}