Csharp MissingMethodException：无法动态创建具有Blazor和依赖项注入的类型的实例

当我try 将依赖项注入与非参数构造函数一起使用时，我在Blazor服务器应用程序中遇到了‘MissingMethodException’MissingMethodException: Cannot dynamically create an instance of type 'Blazor.Pages.Account.Register'. Reason: No parameterless constructor defined.以下是我到目前为止try 过的:

我已经创建了UserService.cs

using Blazor.API.Model;

namespace Blazor.Services
{
    public class UserService
    {
        private readonly HttpClient _httpClient;
        public UserService(HttpClient httpClient)
        {
            _httpClient = httpClient;
        }

        public async Task<bool> RegisterAsync(RegisterModel registerModel)
        {
            try
            {
                var response = await _httpClient.PostAsJsonAsync("/register", registerModel);
                if (response.IsSuccessStatusCode)
                {
                    return true;
                }
                else
                {
                    return false;
                }
            }
            catch
            {
                return false;
            }
        }
    }
}

我已经更新了Program.cs

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
builder.Services.AddRazorPages();
builder.Services.AddServerSideBlazor();


builder.Services.AddScoped<HttpClient>(s =>
{
    var httpClient = new HttpClient
    {
        BaseAddress = new Uri(builder.Configuration.GetSection("ApiBaseUrl").Value)
    };
    return httpClient;
});
builder.Services.AddHttpClient();
builder.Services.AddScoped<UserService>();
var app = builder.Build();

另外，当我将鼠标悬停在builder.Configuration.GetSection("ApiBaseUrl").Value时，我收到错误"Warning CS8604 Possible null reference argument for parameter 'uriString' in 'Uri.Uri(string uriString)'"

和我的注册表.razor.cs

using Blazor.API.Model;
using Blazor.Services;

namespace Blazor.Pages.Account
{
    public partial class Register
    {
        private UserService UserService { get; set; }
        private bool isRegistering = false;
        private bool registrationSuccessful = false;
        private RegisterModel registerModel = new RegisterModel();
        
        public Register(UserService userService)
        {
            UserService = userService;
        }
        

        private async Task HandleValidSubmit()
        {
            // Start the registration process
            isRegistering = true;

            //send the registration request to the server
            bool registrationResult = await UserService.RegisterAsync(registerModel); 

            // Update the registration state
            registrationSuccessful = registrationResult;

            // Stop the registration process
            isRegistering = false;
        }
    }
}

但是，当我导航到此RegisterComponent时，我收到了‘MissingMethodException’错误.我也try 过添加无参数构造函数，但它导致了一个警告:‘不可为空的属性必须包含非空值’.

我如何解决这个问题，并正确使用依赖注入与Blazor组件的非参数构造函数？

这是我的登记簿.剃须刀

@page "/register"

<h3 class="text-center">Register</h3>
<div class="form-container">
<EditForm Model="@registerModel" OnValidSubmit="HandleValidSubmit" >
    <DataAnnotationsValidator />
    <ValidationSummary />

    <div class="form-group">
        <label for="FirstName" class="form-label">First Name</label>
        <InputText id="FirstName" @bind-Value="registerModel.FirstName" class="form-control" />
        <ValidationMessage For="@(() => registerModel.FirstName)" />
    </div>

    <div class="form-group">
        <label for="LastName" class="form-label">Last Name</label>
        <InputText id="LastName" @bind-Value="registerModel.LastName" class="form-control" />
        <ValidationMessage For="@(() => registerModel.LastName)" />
    </div>

    <div class="form-group">
        <label for="Email" class="form-label">Email</label>
        <InputText id="Email" @bind-Value="registerModel.Email" class="form-control" />
        <ValidationMessage For="@(() => registerModel.Email)" />
    </div>

    <div class="form-group">
        <label for="PhoneNumber" class="form-label">Phone Number</label>
        <InputText id="PhoneNumber" @bind-Value="registerModel.PhoneNumber" class="form-control" />
        <ValidationMessage For="@(() => registerModel.PhoneNumber)" />
    </div>

    <div class="form-group">
        <label for="Password" class="form-label">Password</label>
        <InputText id="Password" @bind-Value="registerModel.Password" class="form-control" type="password" />
        <ValidationMessage For="@(() => registerModel.Password)" />
    </div>

        <div class="text-center">
            <button type="submit" class="btn btn-primary" disabled="@isRegistering">
                @if (isRegistering)
                {
                    <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
                    <text>Registering...</text>
                }
                else if (registrationSuccessful)
                {
                    <text>Registration Successful</text>
                }
                else
                {
                    <text>Register</text>
                }
            </button>
        </div>
        <p class="text-center mt-3">
        Already have an account? <a href="/login">Login here</a>
    </p>
</EditForm>
</div>

@code {
   
}

和我的appSetting.json

{
  "Logging": {
    "LogLevel": {
      "Default": "Information",
      "Microsoft.AspNetCore": "Warning"
    }
  },
  "AllowedHosts": "*",
  "ApiBaseUrl": "https://localhost:44330/"
}

我是Blazor服务器应用程序的初学者，目前我正在学习如何在Blazor服务器应用程序中连接和交互API.具体地说，我正在致力于实现用户注册和登录功能.然而，我在设置HttpClient和为注册过程建立正确的流程方面遇到了困难，如本文所述.