1. 在ASP.NET Core 3.1 Web应用程序的Startup.cs文件中配置并启用身份验证：

public void ConfigureServices(IServiceCollection services)
{
    // 添加身份验证服务
    services.AddAuthentication(options =>
    {
        options.DefaultScheme = CookieAuthenticationDefaults.AuthenticationScheme;
    })
    .AddCookie(options =>
    {
        options.Cookie.Name = "AuthCookie";
        options.LoginPath = "/Account/Login";
        options.AccessDeniedPath = "/Account/AccessDenied";
        options.ExpireTimeSpan = TimeSpan.FromDays(30);
        options.SlidingExpiration = true;
    });
}

public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    // 启用身份验证中间件
    app.UseAuthentication();
}

2. 创建一个控制器，以获取用户设备信息：

public class UserController : Controller
{
    private readonly UserManager _userManager;
    private readonly SignInManager _signInManager;

    public UserController(UserManager userManager, SignInManager signInManager)
    {
        _userManager = userManager;
        _signInManager = signInManager;
    }

    public async Task GetDevices()
    {
        var user = await _userManager.GetUserAsync(User);
        var logins = await _signInManager.GetExternalAuthenticationSchemesAsync();
        var devices = new List();

        foreach (var login in logins)
        {
            var info = await _signInManager.GetExternalLoginInfoAsync(login.Name);
            if (info != null && info.Principal.HasClaim(x => x.Type.EndsWith("sid")))
            {
                devices.Add(info.ProviderDisplayName);
            }
        }

        return View(devices);
    }
}

3. 创建一个视图来显示设备信息：

@model IEnumerable

用户设备信息：

@if (Model.Any())
{
    

        @foreach (var device in Model)
        {
            
@device
        }
    
}
else
{
    
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