Реализовал Unity DI

SecuritySystem/SecuritySystemContracts/DI/UnityDependencyContainer.cs

@@ -0,0 +1,38 @@
+
+using Microsoft.Extensions.Logging;
+using Unity;
+using Unity.Microsoft.Logging;
+
+namespace SecuritySystemContracts.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, U>(bool isSingle) where U : class, T where T : class
+        {
+            _container.RegisterType<T, U>(isSingle ? TypeLifetime.Singleton : TypeLifetime.Transient);
+        }
+
+        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>();
+        }
+    }
+}

SecuritySystem/SecuritySystemContracts/SecuritySystemContracts.csproj

@@ -9,6 +9,8 @@
 
   <ItemGroup>
     <PackageReference Include="Microsoft.Extensions.Logging" Version="7.0.0" />
+    <PackageReference Include="Unity" Version="5.11.10" />
+	<PackageReference Include="Unity.Microsoft.Logging" Version="5.11.1" />
   </ItemGroup>
 
   <ItemGroup>

SecuritySystem/SecuritySystemFileImplement/Models/Order.cs

@@ -63,7 +63,7 @@ namespace SecuritySystemFileImplement.Models
                 Status = (OrderStatus)Enum.Parse(typeof(OrderStatus), element.Element("Status")!.Value),
                 DateCreate = Convert.ToDateTime(element.Element("DateCreate")!.Value),
                 DateImplement = string.IsNullOrEmpty(element.Element("DateImplement")!.Value) ? null : Convert.ToDateTime(element.Element("DateImplement")!.Value),
-                ImplementerId = Convert.ToInt32(element.Element("ImplementerId")!.Value),
+                ImplementerId = string.IsNullOrEmpty(element.Element("ImplementerId")!.Value) ? null : Convert.ToInt32(element.Element("ImplementerId")!.Value),
             };
         }