implement the Mailservice

ConsoleApp1/ConsoleApp1.csproj

@@ -7,4 +7,10 @@
         <Nullable>enable</Nullable>
     </PropertyGroup>
 
+    <ItemGroup>
+      <None Update="appsettings.json">
+        <CopyToOutputDirectory>Always</CopyToOutputDirectory>
+      </None>
+    </ItemGroup>
+
 </Project>

ConsoleApp1/MailService.cs

@@ -0,0 +1,35 @@
+using System.Net;
+using System.Net.Mail;
+
+namespace ConsoleApp1;
+
+public class MailService
+{
+    private readonly SmtpSettings _smtpSettings;
+
+    public MailService(SmtpSettings smtpSettings)
+    {
+        _smtpSettings = smtpSettings;
+    }
+
+    public void SendEmail(string to, string subject, string body)
+    {
+        using (var client = new SmtpClient(_smtpSettings.SmtpServer, _smtpSettings.SmtpPort))
+        {
+            client.Credentials = new NetworkCredential(_smtpSettings.SmtpUser, _smtpSettings.SmtpPassword);
+            client.EnableSsl = true;
+
+            var mailMessage = new MailMessage
+            {
+                From = new MailAddress(_smtpSettings.SmtpFrom),
+                Subject = subject,
+                Body = body,
+                IsBodyHtml = true,
+            };
+
+            mailMessage.To.Add(to);
+
+            client.Send(mailMessage);
+        }
+    }
+}

ConsoleApp1/Program.cs

@@ -1,9 +1,32 @@
-namespace ConsoleApp1;
+using System;
+using System.IO;
+using System.Text.Json;
 
-class Program
+namespace ConsoleApp1
 {
+    class Program
+    {
         static void Main(string[] args)
         {
-        Console.WriteLine("Hello, World!");
+            string jsonFilePath = "appsettings.json";
+            string jsonString = File.ReadAllText(jsonFilePath);
+
+            var options = new JsonSerializerOptions
+            {
+                PropertyNameCaseInsensitive = true
+            };
+
+            SmtpSettings? smtpSettings = JsonSerializer.Deserialize<SmtpSettings>(jsonString, options);
+
+            if (smtpSettings is null)
+            {
+                Console.WriteLine("Failed to deserialize SmtpSettings");
+                return;
+            }
+            
+            MailService mailService = new MailService(smtpSettings);
+            mailService.SendEmail("user@user.com", "Hello World", "Hello World from C#!");
+
+        }
     }
 }

ConsoleApp1/SmtpSettings.cs

@@ -0,0 +1,10 @@
+namespace ConsoleApp1;
+
+public class SmtpSettings
+{
+    public string SmtpServer { get; set; }
+    public int SmtpPort { get; set; }
+    public string SmtpUser { get; set; }
+    public string SmtpPassword { get; set; }
+    public string SmtpFrom { get; set; }
+}