如何使用razor view ASP .Net Core从JWT声明角色

// Startup.cs

public void ConfigureServices(IServiceCollection services)
{
    // 配置身份验证
    services.AddAuthentication(options =>
    {
        options.DefaultAuthenticateScheme = JwtBearerDefaults.AuthenticationScheme;
        options.DefaultChallengeScheme = JwtBearerDefaults.AuthenticationScheme;
    })
    .AddJwtBearer(options =>
    {
        options.TokenValidationParameters = new TokenValidationParameters
        {
            ValidateIssuer = true,
            ValidateAudience = true,
            ValidateLifetime = true,
            ValidateIssuerSigningKey = true,
            ValidIssuer = "your_issuer",
            ValidAudience = "your_audience",
            IssuerSigningKey = new SymmetricSecurityKey(Encoding.UTF8.GetBytes("your_secret_key"))
        };
    });

    // 配置授权策略
    services.AddAuthorization(options =>
    {
        options.AddPolicy("AdminOnly", policy => policy.RequireRole("admin"));
    });

    services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_2);
}

// HomeController.cs

[Authorize(Roles = "admin")]
public class HomeController : Controller
{
    public IActionResult Index()
    {
        return View();
    }
}

// Index.cshtml

@{
    ViewData["Title"] = "Home Page";
}

@if (User.IsInRole("admin"))
{
    <h1>Welcome, Admin!</h1>
}
else
{
    <h1>Welcome, Guest!</h1>
}