Добавил юнити контейнер

IceCreamShop/IceCreamShop/ViewMailForm.Designer.cs

@@ -49,7 +49,7 @@
 			ClientSize = new Size(800, 450);
 			Controls.Add(dataGridView);
 			Name = "ViewMailForm";
-			Text = "ViewMailForm";
+			Text = "Просмотр почты";
 			Load += ViewMailForm_Load;
 			((System.ComponentModel.ISupportInitialize)dataGridView).EndInit();
 			ResumeLayout(false);

IceCreamShop/IceCreamShopContracts/DI/DependencyManager.cs

@@ -14,7 +14,7 @@ namespace IceCreamShopContracts.DI
 		private static readonly object _locjObject = new();
 		private DependencyManager()
 		{
-			_dependencyManager = new ServiceDependencyContainer();
+			_dependencyManager = new UnityDependencyContainer();
 		}
 		public static DependencyManager Instance
 		{

IceCreamShop/IceCreamShopContracts/DI/UnityDependencyContainer.cs

@@ -0,0 +1,39 @@
+using IceCreamShopContracts.DI;
+using Microsoft.Extensions.Logging;
+using Unity;
+using Unity.Microsoft.Logging;
+
+namespace IceCreamShopContracts.DI
+{
+	public class UnityDependencyContainer : IDependencyContainer
+	{
+		private readonly IUnityContainer _container;
+
+		public UnityDependencyContainer()
+		{
+			_container = new UnityContainer();
+		}
+
+		public void AddLogging(Action<ILoggingBuilder> configure)
+		{
+			var factory = LoggerFactory.Create(configure);
+			_container.AddExtension(new LoggingExtension(factory));
+		}
+
+		public void RegisterType<T>(bool isSingle) where T : class
+		{
+			_container.RegisterType<T>(isSingle ? TypeLifetime.Singleton : TypeLifetime.Transient);
+
+		}
+
+		public T Resolve<T>()
+		{
+			return _container.Resolve<T>();
+		}
+
+		void IDependencyContainer.RegisterType<T, U>(bool isSingle)
+		{
+			_container.RegisterType<T, U>(isSingle ? TypeLifetime.Singleton : TypeLifetime.Transient);
+		}
+	}
+}

IceCreamShop/IceCreamShopContracts/IceCreamShopContracts.csproj

@@ -8,6 +8,9 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Logging" Version="8.0.0" />
+    <PackageReference Include="Unity" Version="5.11.10" />
+    <PackageReference Include="Unity.Container" Version="5.11.11" />
+    <PackageReference Include="Unity.Microsoft.Logging" Version="5.11.1" />
   </ItemGroup>
 
   <ItemGroup>