问Blazor Server:自定义登录页

EN

@page "/"
@using Microsoft.AspNetCore.Identity
@using Blazor.PMC.Models.Identity
@inject UserManager<ApplicationUser> _userManager
@inject SignInManager<ApplicationUser> _signInManager

<AuthorizeView>
    <Authorized>
        <h1>Hello @context.User.Identity.Name !!</h1>
        <p>Welcome to your new app.</p>
    </Authorized>
    <NotAuthorized>
        <div class="form-group row m-b-15">
            <label class="col-md-3 col-form-label">Username</label>
            <div class="col-md-7">
                <input @bind-value="Username" type="text" class="form-control" placeholder=" Enter username" />
            </div>
        </div>
        <div class="form-group row m-b-15">
            <label class="col-md-3 col-form-label">Password</label>
            <div class="col-md-7">
                <input @bind-value="Password" type="text" class="form-control" placeholder="Enter password" />
            </div>
        </div>
        <button type="submit" @onclick="LoginUser" class="btn btn-sm btn-primary m-r-5">Login</button>
    </NotAuthorized>
</AuthorizeView>

<br />

@Message

@code {
    string Username;
    string Password;
    string Message;

    private async void LoginUser()
    {
        var user = await _userManager.FindByNameAsync(Username);
        if (user == null)
            Message = "User does not exist";

        var singInResult = await _signInManager.CheckPasswordSignInAsync(user, Password, false);
        if (!singInResult.Succeeded)
            Message = "Invalid password";
        else
            await _signInManager.SignInAsync(user, false); // Error occurs here

        await InvokeAsync(() => StateHasChanged())
                    .ConfigureAwait(false);
    }
}