Check out example codes for "asp net core send email async". It will help you in understanding the concepts better.

Code Example 1

public interface IEmailSender
{
    Task SendEmailAsync(string email, string subject, string message);
}

public class EmailSender : IEmailSender
{
    public Task SendEmailAsync(string email, string subject, string message)
    {
        return Task.CompletedTask;
    }
}

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