在ASP.NET核心中以视图方式登录UserName

services.AddIdentity<IdentityUser, IdentityRole>()
    .AddEntityFrameworkStores<ApplicationDbContext>()
    .AddDefaultTokenProviders();

<form asp-controller="Account" asp-action="Login" method="post">
    <div class="form-group">
        <label for="username">Username:</label>
        <input type="text" id="username" name="username" class="form-control" />
    </div>
    <div class="form-group">
        <label for="password">Password:</label>
        <input type="password" id="password" name="password" class="form-control" />
    </div>
    <button type="submit" class="btn btn-primary">Login</button>
</form>

[HttpPost]
public async Task<IActionResult> Login(string username, string password)
{
    // 验证用户名和密码
    var result = await _signInManager.PasswordSignInAsync(username, password, false, false);
    
    if (result.Succeeded)
    {
        // 登录成功，重定向到首页
        return RedirectToAction("Index", "Home");
    }
    else
    {
        // 登录失败，显示错误消息
        ModelState.AddModelError("", "Invalid username or password");
        return View();
    }
}

@if (!ViewData.ModelState.IsValid)
{
    <div class="alert alert-danger">
        @foreach (var error in ViewData.ModelState.Values.SelectMany(v => v.Errors))
        {
            <span>@error.ErrorMessage</span><br />
        }
    </div>
}