I am not sure why I am getting the following Unhandled exception error while running my code:
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From looking at other similar issues here:
stackoverflow.com
stackoverflow.com
The issue looks to be within the parameters being passed to the services.Addscoped method.
I cannot see that there is anything wrong with that line of code within my Startup class:
services.AddScoped<IBlogEmailSender, EmailService>();
Can anyone tell where the error is coming from?
Thanks.
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From looking at other similar issues here:
Dependency Injection error: Unable to resolve service for type while attempting to activate, while class is registered
I created an .NET Core MVC application and use Dependency Injection and Repository Pattern to inject a repository to my controller. However, I am getting an error: InvalidOperationException: Unabl...
stackoverflow.com
Unable to resolve service for type while attempting to activate
In my ASP.NET Core application, I get the following error: InvalidOperationException: Unable to resolve service for type 'Cities.Models.IRepository' while attempting to activate 'Cities.Controllers.
stackoverflow.com
The issue looks to be within the parameters being passed to the services.Addscoped method.
I cannot see that there is anything wrong with that line of code within my Startup class:
services.AddScoped<IBlogEmailSender, EmailService>();
Can anyone tell where the error is coming from?
Thanks.
C#:
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using TheBlogProject.Data;
using TheBlogProject.Models;
using TheBlogProject.Services;
using TheBlogProject.ViewModels;
namespace TheBlogProject
{
public class Startup
{
public Startup(IConfiguration configuration)
{
Configuration = configuration;
}
public IConfiguration Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
//services.AddDbContext<ApplicationDbContext>(options =>
// options.UseSqlServer(Configuration.GetConnectionString("DefaultConnection")));
services.AddMvc();
services.AddDatabaseDeveloperPageExceptionFilter();
services.AddDbContext<ApplicationDbContext>(options =>
options.UseNpgsql(Configuration.GetConnectionString("DefaultConnection")));
services.AddIdentity<BlogUser, IdentityRole>(options => options.SignIn.RequireConfirmedAccount = true)
.AddDefaultUI()
.AddDefaultTokenProviders()
.AddEntityFrameworkStores<ApplicationDbContext>();
services.AddControllersWithViews();
services.AddRazorPages();
// Register my custom DataService class
services.AddScoped<DataService>();
//register a preconfigured instance of the mailsetting class
services.Configure<MailSettings>(Configuration.GetSection("MailSettings"));
services.AddScoped<IBlogEmailSender, EmailService>();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
app.UseMigrationsEndPoint();
}
else
{
app.UseExceptionHandler("/Home/Error");
// The default HSTS value is 30 days. You may want to change this for production scenarios, see [URL='https://aka.ms/aspnetcore-hsts']Enforce HTTPS in ASP.NET Core[/URL].
app.UseHsts();
}
app.UseHttpsRedirection();
app.UseStaticFiles();
app.UseRouting();
app.UseAuthentication();
app.UseAuthorization();
app.UseEndpoints(endpoints =>
{
endpoints.MapControllerRoute(
name: "default",
pattern: "{controller=Home}/{action=Index}/{id?}");
endpoints.MapRazorPages();
});
}
}
}
C#:
using MailKit.Net.Smtp;
using MailKit.Security;
using Microsoft.Extensions.Options;
using MimeKit;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using TheBlogProject.ViewModels;
namespace TheBlogProject.Services
{
public class EmailService : IBlogEmailSender
{
private readonly MailSettings _mailSettings;
public EmailService(IOptions<MailSettings> mailSettings)
{
_mailSettings = mailSettings.Value;
}
public Task SendContactEmailAsync(string emailForm, string name, string subject, string htmlMessage)
{
throw new NotImplementedException();
}
public async Task SendEmailAsync(string emailTo, string subject, string htmlMessage)
{
var email = new MimeMessage();
email.Sender = MailboxAddress.Parse(_mailSettings.Mail);
email.To.Add(MailboxAddress.Parse(emailTo));
email.Subject = subject;
//var builder = new BodyBuilder();
//builder.HtmlBody = htmlMessage;
var builder = new BodyBuilder()
{
HtmlBody = htmlMessage
};
email.Body = builder.ToMessageBody();
using var smtp = new SmtpClient();
smtp.Connect(_mailSettings.Host, _mailSettings.Port, SecureSocketOptions.StartTls);
smtp.Authenticate(_mailSettings.Mail, _mailSettings.Password);
await smtp.SendAsync(email);
smtp.Disconnect(true);
}
}
}
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using Microsoft.AspNetCore.Identity.UI.Services;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
namespace TheBlogProject.Services
{
public interface IBlogEmailSender : IEmailSender
{
Task SendContactEmailAsync(string emailForm, string name, string subject, string htmlMessage);
}
}
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using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Text.Encodings.Web;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Authentication;
using Microsoft.AspNetCore.Identity;
using Microsoft.AspNetCore.Identity.UI.Services;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.Extensions.Logging;
namespace TheBlogProject.Areas.Identity.Pages.Account
{
[AllowAnonymous]
public class LoginModel : PageModel
{
private readonly UserManager<IdentityUser> _userManager;
private readonly SignInManager<IdentityUser> _signInManager;
private readonly ILogger<LoginModel> _logger;
public LoginModel(SignInManager<IdentityUser> signInManager,
ILogger<LoginModel> logger,
UserManager<IdentityUser> userManager)
{
_userManager = userManager;
_signInManager = signInManager;
_logger = logger;
}
[BindProperty]
public InputModel Input { get; set; }
public IList<AuthenticationScheme> ExternalLogins { get; set; }
public string ReturnUrl { get; set; }
[TempData]
public string ErrorMessage { get; set; }
public class InputModel
{
[Required]
[EmailAddress]
public string Email { get; set; }
[Required]
[DataType(DataType.Password)]
public string Password { get; set; }
[Display(Name = "Remember me?")]
public bool RememberMe { get; set; }
}
public async Task OnGetAsync(string returnUrl = null)
{
if (!string.IsNullOrEmpty(ErrorMessage))
{
ModelState.AddModelError(string.Empty, ErrorMessage);
}
returnUrl ??= Url.Content("~/");
// Clear the existing external cookie to ensure a clean login process
await HttpContext.SignOutAsync(IdentityConstants.ExternalScheme);
ExternalLogins = (await _signInManager.GetExternalAuthenticationSchemesAsync()).ToList();
ReturnUrl = returnUrl;
}
public async Task<IActionResult> OnPostAsync(string returnUrl = null)
{
returnUrl ??= Url.Content("~/");
ExternalLogins = (await _signInManager.GetExternalAuthenticationSchemesAsync()).ToList();
if (ModelState.IsValid)
{
// This doesn't count login failures towards account lockout
// To enable password failures to trigger account lockout, set lockoutOnFailure: true
var result = await _signInManager.PasswordSignInAsync(Input.Email, Input.Password, Input.RememberMe, lockoutOnFailure: false);
if (result.Succeeded)
{
_logger.LogInformation("User logged in.");
return LocalRedirect(returnUrl);
}
if (result.RequiresTwoFactor)
{
return RedirectToPage("./LoginWith2fa", new { ReturnUrl = returnUrl, RememberMe = Input.RememberMe });
}
if (result.IsLockedOut)
{
_logger.LogWarning("User account locked out.");
return RedirectToPage("./Lockout");
}
else
{
ModelState.AddModelError(string.Empty, "Invalid login attempt.");
return Page();
}
}
// If we got this far, something failed, redisplay form
return Page();
}
}
}
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