asp.net-core 登录视图组件
示例
默认项目模板将创建一个局部视图_LoginPartial.cshtml，其中包含一些逻辑，用于查找用户是否已登录并查找其用户名。
由于视图组件可能更合适（因为涉及逻辑，甚至注入了2个服务），因此以下示例显示了如何将LoginPartial转换为视图组件。
查看组件类
public class LoginViewComponent : ViewComponent
{
private readonly SignInManager<ApplicationUser> signInManager;
private readonly UserManager<ApplicationUser> userManager;
public LoginViewComponent(SignInManager<ApplicationUser> signInManager, UserManager<ApplicationUser> userManager)
{
this.signInManager= signInManager;
this.userManager= userManager;
}
public async Task<IViewComponentResult> InvokeAsync()
{
if (signInManager.IsSignedIn(this.User as ClaimsPrincipal))
{
return View("SignedIn", await userManager.GetUserAsync(this.User as ClaimsPrincipal));
}
return View("SignedOut");
}
}登录视图（在〜/Views/Shared/Components/Login/SignedIn.cshtml中）
@model WebApplication1.Models.ApplicationUser
<form asp-area="" asp-controller="Account" asp-action="LogOff" method="post" id="logoutForm" class="navbar-right">
<ul class="nav navbar-nav navbar-right">
<li>
<a asp-area="" asp-controller="Manage" asp-action="Index" title="Manage">Hello @Model.UserName!</a>
</li>
<li>
<button type="submit" class="btn btn-link navbar-btn navbar-link">Log off</button>
</li>
</ul>
</form>SignedOut视图（在〜/Views/Shared/Components/Login/SignedOut.cshtml中）
<ul class="nav navbar-nav navbar-right">
<li><a asp-area="" asp-controller="Account" asp-action="Register">Register</a></li>
<li><a asp-area="" asp-controller="Account" asp-action="Login">Log in</a></li>
</ul>从_Layout.cshtml调用
@await Component.InvokeAsync("Login")