揭秘.NET 11：Blazor 在客户端性能优化与安全强化

// 定义一个简单的Blazor组件
using Microsoft.AspNetCore.Components;

public partial class Counter : ComponentBase
{
    private int currentCount = 0;

    private void IncrementCount()
    {
        currentCount++;
    }
}

<!-- Counter.razor -->
<div>
    <p>Current count: @currentCount</p>
    <button @onclick="IncrementCount">Click me</button>
</div>

// 定义一个按需加载的组件
using Microsoft.AspNetCore.Components;

public partial class LazyLoadedComponent : ComponentBase
{
    // 模拟一些复杂的初始化逻辑
    protected override async Task OnInitializedAsync()
    {
        await Task.Delay(2000);
    }
}

<!-- MainPage.razor -->
<PageTitle>Home</PageTitle>
<h1>Welcome</h1>
<button @onclick="LoadComponent">Load Lazy Component</button>

@if (isComponentLoaded)
{
    <LazyLoadedComponent />
}

@code {
    private bool isComponentLoaded = false;

    private void LoadComponent()
    {
        isComponentLoaded = true;
    }
}

using Microsoft.AspNetCore.Components;
using Microsoft.AspNetCore.Components.Forms;

public partial class LoginForm : ComponentBase
{
    private string username = "";
    private string password = "";

    private void HandleValidSubmit()
    {
        // 这里对用户名和密码进行验证和处理
        // Blazor会自动对输入进行编码，防止注入攻击
    }
}

<!-- LoginForm.razor -->
<EditForm Model=this OnValidSubmit="HandleValidSubmit">
    <DataAnnotationsValidator />
    <div>
        <label for="username">Username:</label>
        <InputText id="username" @bind - Value="username" />
    </div>
    <div>
        <label for="password">Password:</label>
        <InputText id="password" @bind - Value="password" Type="password" />
    </div>
    <button type="submit">Login</button>
</EditForm>

// 配置身份验证服务
using Microsoft.AspNetCore.Components.Authorization;
using Microsoft.Extensions.DependencyInjection;

public static class AuthServiceCollectionExtensions
{
    public static IServiceCollection AddCustomAuth(this IServiceCollection services)
    {
        services.AddAuthorizationCore();
        services.AddScoped<AuthenticationStateProvider, CustomAuthStateProvider>();
        return services;
    }
}

// 自定义身份验证状态提供器
using Microsoft.AspNetCore.Components.Authorization;
using System.Security.Claims;
using System.Threading.Tasks;

public class CustomAuthStateProvider : AuthenticationStateProvider
{
    public override async Task<AuthenticationState> GetAuthenticationStateAsync()
    {
        // 这里模拟获取用户身份信息
        var identity = new ClaimsIdentity(new[] { new Claim(ClaimTypes.Name, "user1") }, "Custom");
        var user = new ClaimsPrincipal(identity);
        return new AuthenticationState(user);
    }
}

<!-- 授权组件示例 -->
<AuthorizeView Roles="admin">
    <p>Only admins can see this.</p>
</AuthorizeView>