这个问题没有简短的答案。为了识别用户，您需要实现身份验证方案，然后与Blazor的AuthenticationStateProvider集成。
从阅读本系列文章开始：
https://chrissainty.com/series/securing-your-blazor-apps/
此外，官方文件在评论中指出：
https://learn.microsoft.com/en-us/aspnet/core/blazor/security
实际上，这里有几个主题可以彼此分开：
1.学习Blazor。
1.学习ASP.NET核心认证和授权。
1.学习如何将Blazor与AuthenticationStateProvider集成。
1.了解您可用的各种身份验证方案选项，例如Cookie、承载令牌、JWT等。
1.了解各种身份提供者，无论是本地（EF核心身份，相邻的Web API或数据库）还是外部（Azure，Auth 0，社交媒体平台等）。
作为一个初学者，你可能应该坚持使用一些应用内/本地身份验证提供程序，只是为了开始和熟悉一些基本的身份验证概念。应用内意味着，您可以使用本地数据库，可能是EF Core Identity数据库，而不是尝试与外部提供商集成。
最终，您用于学习/爱好项目目的的东西可能不会在真实的世界中飞行，当涉及到安全性和性能时，这取决于您的需求。
请注意，如果您发现自己编写了自己的哈希/加密算法来存储用户的敏感数据或密码，那么您就做错了。这可能不是你的项目的主要目的，你不应该试图发明已经存在的东西。
也许为了更直接地帮助您入门，请参阅此存储库--https://github.com/CodeFontana/BlazorSimpleAuthDemo
这是我能想到的最基本的用户身份验证演示，基于.NET 7.0的vanilla Blazor Server模板。
为了在Stack Overflow上回答的完整性，我将在这里发布代码的相关部分。
Program.cs

using BlazorSimpleAuth.Authentication;
using BlazorSimpleAuth.Data;
using Microsoft.AspNetCore.Components.Authorization;
WebApplicationBuilder builder = WebApplication.CreateBuilder(args);
builder.Services.AddRazorPages();
builder.Services.AddServerSideBlazor();
builder.Services.AddSingleton<WeatherForecastService>();
builder.Services.AddScoped<IAuthenticationService, AuthenticationService>();
builder.Services.AddScoped<AuthenticationStateProvider, SimpleAuthStateProvider>();
WebApplication app = builder.Build();
if (app.Environment.IsDevelopment() == false)
{
    app.UseExceptionHandler("/Error");
    app.UseHsts();
}
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseRouting();
app.UseAuthentication();
app.UseAuthorization();
app.MapBlazorHub();
app.MapFallbackToPage("/_Host");
app.Run();

App.razor:

<CascadingAuthenticationState>
    <Router AppAssembly="@typeof(App).Assembly">
        <Found Context="routeData">
            <AuthorizeRouteView Context="AuthContext" RouteData="@routeData" DefaultLayout="@typeof(MainLayout)" >
                <NotAuthorized>
                    You are not authorized, please login.
                </NotAuthorized>
            </AuthorizeRouteView>
        </Found>
        <NotFound>
            <PageTitle>Not found</PageTitle>
            <LayoutView Layout="@typeof(MainLayout)">
                <p role="alert">Sorry, there's nothing at this address.</p>
            </LayoutView>
        </NotFound>
    </Router>
</CascadingAuthenticationState>

Index.razor

@page "/"
@inject IAuthenticationService Auth
<PageTitle>Index</PageTitle>
<h1>Hello, world!</h1>
Welcome to your new app.
<AuthorizeView>
    <Authorized>
        <div class="mt-3">
            <p>Hello, @context.User.Identity!.Name!</p>
            <button type="submit" class="btn btn-primary" @onclick="OnLogout">
                <text>Logout</text>
            </button>
        </div>
    </Authorized>
    <NotAuthorized>
        <Login />
    </NotAuthorized>
</AuthorizeView>
@code {
    private void OnLogout()
    {
        // Logout user and update application state
        Auth.Logout();
    }
}

Login.razor:

@using System.Security.Claims;
@inject NavigationManager Nav
@inject IAuthenticationService Auth
@inject AuthenticationStateProvider AuthState
@attribute [AllowAnonymous]
<div class="container mt-3">
    <div class="row d-flex justify-content-center">
        <div class="col-12 col-lg-6">
            <EditForm Model="@_loginUser" OnValidSubmit="() => OnLogin()">
                <DataAnnotationsValidator />
                <div class="input-group mb-3">
                    <span class="input-group-text" style="width: 100px;">Username</span>
                    <InputText class="form-control" @bind-Value="_loginUser.Username" disabled="@_authenticating" />
                    <div class="text-danger">
                        <ValidationMessage For="@(() => _loginUser.Username)" />
                    </div>
                </div>
                <div class="input-group mb-3">
                    <span class="input-group-text" style="width: 100px;">Password</span>
                    <InputText class="form-control" type="password" @bind-Value="_loginUser.Password" disabled="@_authenticating" />
                    <div class="text-danger">
                        <ValidationMessage For="@(() => _loginUser.Password)" />
                    </div>
                </div>
                <button type="submit" class="btn btn-primary w-100" disabled="@_authenticating">
                    <text>Login</text>
                </button>
                @if (_loginFailed)
                {
                    <div class="alert alert-danger mt-3" role="alert">
                        <strong>Invalid username or password</strong>
                    </div>
                }
            </EditForm>
        </div>
    </div>
</div>
@code {
    private LoginUserModel _loginUser = new();
    private bool _authenticating = false;
    private bool _loginFailed = false;
    protected override async Task OnInitializedAsync()
    {
        AuthenticationState authState = await AuthState.GetAuthenticationStateAsync();
        ClaimsPrincipal user = authState.User;
        if (user is not null 
            && user.Identity is not null
            && user.Identity.IsAuthenticated)
        {
            Nav.NavigateTo("");
        }
    }
    private void OnLogin()
    {
        _loginFailed = false;
        // Authenticate user and update application state
        bool result = Auth.Login(_loginUser);
        if(!result)
        {
            _loginFailed = true;
        }
    }
}

AuthenticationService.cs:

using BlazorSimpleAuth.Models;
using Microsoft.AspNetCore.Components.Authorization;
namespace BlazorSimpleAuth.Authentication;
public class AuthenticationService : IAuthenticationService
{
    private readonly AuthenticationStateProvider _authStateProvider;
    public AuthenticationService(AuthenticationStateProvider authStateProvider)
    {
        _authStateProvider = authStateProvider;
    }
    public bool Login(LoginUserModel loginUser)
    {
        ArgumentNullException.ThrowIfNull(loginUser);
        ArgumentNullException.ThrowIfNull(loginUser.Username);
        ArgumentNullException.ThrowIfNull(loginUser.Password);
        // This code here would never fly in production, and is for demo purposes only. This is
        // the spot you would farm out your authentication to a proper identity provider.
        if (loginUser.Username.Equals("admin", StringComparison.InvariantCultureIgnoreCase)
            && loginUser.Password.Equals("password", StringComparison.InvariantCultureIgnoreCase))
        {
            ((SimpleAuthStateProvider)_authStateProvider).NotifyLoginUser(loginUser);
            return true;
        }
        return false;
    }
    public void Logout()
    {
        ((SimpleAuthStateProvider)_authStateProvider).NotifyUserLogout();
    }
}

SimpleAuthStateProvider.cs:

using BlazorSimpleAuth.Models;
using Microsoft.AspNetCore.Components.Authorization;
using System.Security.Claims;
namespace BlazorSimpleAuth.Authentication;
public sealed class SimpleAuthStateProvider : AuthenticationStateProvider
{
    private readonly AuthenticationState _anonymous;
    private ClaimsIdentity _identity = new();
    public SimpleAuthStateProvider()
    {
        _anonymous = new AuthenticationState(new ClaimsPrincipal(new ClaimsIdentity()));
    }
    public override Task<AuthenticationState> GetAuthenticationStateAsync()
    {
        ClaimsPrincipal user = new(_identity);
        return Task.FromResult(new AuthenticationState(user));
    }
    public void NotifyLoginUser(LoginUserModel loginUser)
    {
        ArgumentNullException.ThrowIfNull(loginUser);
        ArgumentNullException.ThrowIfNull(loginUser.Username);
        ArgumentNullException.ThrowIfNull(loginUser.Password);
        _identity = new ClaimsIdentity(new[] { new Claim(ClaimTypes.Name, loginUser.Username) }, "SimpleDemo");
        ClaimsPrincipal user = new(_identity);
        NotifyAuthenticationStateChanged(Task.FromResult(new AuthenticationState(user)));
    }
    public void NotifyUserLogout()
    {
        _identity = new ClaimsIdentity();
        NotifyAuthenticationStateChanged(Task.FromResult(_anonymous));
    }
}

此外，如果您想查看Blazor Dating应用程序的示例实现，用于演示/教育/非现实世界的目的，您可以查看此存储库：https://github.com/CodeFontana/DatingApp
然而，这使用Blazor WebAssembly作为前端/客户端，并由Web API支持，该API使用EF Core管理所有数据，包括应用内用户身份管理。
无论如何，希望这能帮助你找到正确的方向。