Fix

ComputerStoreBusinessLogic/BusinessLogic/ConsignmentLogic.cs

@@ -97,7 +97,6 @@ namespace ComputerStoreBusinessLogic.BusinessLogic
             if (model == null) { return; }
             if (!withParams) { return; }
             if (model.Price <= 0) { throw new ArgumentNullException("Invalid consignment's price", nameof(model)); }
-            if (string.IsNullOrEmpty(model.OrderID.ToString())) { throw new ArgumentNullException("Invalid Consignment's order ID", nameof(model)); }
 
             _logger.LogInformation("Consignment. Consignment ID:{ ID}. Order ID:{ OrderID}.", model.ID, model.OrderID);
         }

ComputerStoreBusinessLogic/BusinessLogic/RequestLogic.cs

@@ -97,7 +97,6 @@ namespace ComputerStoreBusinessLogic.BusinessLogic
             if (model == null) { return; }
             if (!withParams) { return; }
             if (model.Price <= 0) { throw new ArgumentNullException("Invalid request's price", nameof(model)); }
-            if (string.IsNullOrEmpty(model.OrderID.ToString())) { throw new ArgumentNullException("Invalid Request's order ID", nameof(model)); }
 
             _logger.LogInformation("Request. Request ID:{ ID}. Order ID: { OrderID}. PC ID: { PCID}", model.ID, model.OrderID, model.PCID);
         }

ComputerStoreContracts/BindingModels/ConsignmentBindingModel.cs

@@ -10,7 +10,7 @@ namespace ComputerStoreContracts.BindingModels
     public class ConsignmentBindingModel : IConsignmentModel
     {
         public int ID { get; set; }
-        public int OrderID { get; set; }
+        public int? OrderID { get; set; }
         public double Price { get; set; }
         public Dictionary<int, (IProductModel, int)> ConsignmentProducts { get; set; } = new();
     }

ComputerStoreContracts/BindingModels/RequestBindingModel.cs

@@ -10,7 +10,7 @@ namespace ComputerStoreContracts.BindingModels
     public class RequestBindingModel : IRequestModel
     {
         public int ID { get; set; }
-        public int OrderID { get; set; }
+        public int? OrderID { get; set; }
         public double Price { get; set; }
         public int? PCID { get; set; }
 

ComputerStoreContracts/ViewModels/ConsignmentViewModel.cs

@@ -13,7 +13,7 @@ namespace ComputerStoreContracts.ViewModels
         [DisplayName("Consignment ID")]
         public int ID { get; set; }
         [DisplayName("Order ID")]
-        public int OrderID { get; set; }
+        public int? OrderID { get; set; }
         [DisplayName("Price")]
         public double Price { get; set; }
 

ComputerStoreContracts/ViewModels/RequestViewModel.cs

@@ -13,7 +13,7 @@ namespace ComputerStoreContracts.ViewModels
         [DisplayName("Request ID")]
         public int ID { get; set; }
         [DisplayName("Order ID")]
-        public int OrderID { get; set; }
+        public int? OrderID { get; set; }
         [DisplayName("Price")]
         public double Price { get; set; }
 

ComputerStoreDataModels/Models/IConsignmentModel.cs

@@ -8,7 +8,7 @@ namespace ComputerStoreDataModels.Models
 {
     public interface IConsignmentModel : IID
     {
-        int OrderID { get; }
+        int? OrderID { get; }
         double Price { get; }
         Dictionary<int, (IProductModel, int)> ConsignmentProducts { get; }
     }

ComputerStoreDataModels/Models/IRequestModel.cs

@@ -8,7 +8,7 @@ namespace ComputerStoreDataModels.Models
 {
     public interface IRequestModel : IID
     {
-        int OrderID { get; }
+        int? OrderID { get; }
         int? PCID { get; }
         double Price { get; }
 

ComputerStoreDatabaseImplement/Models/Consignment.cs

@@ -16,8 +16,7 @@ namespace ComputerStoreDatabaseImplement.Models
     {
         public int ID { get; private set; }
 
-        [Required]
-        public int OrderID { get; private set; }
+        public int? OrderID { get; private set; }
         public virtual Order Order { get; set; }
 
         [Required]
@@ -68,6 +67,7 @@ namespace ComputerStoreDatabaseImplement.Models
                 return;
             }
             Price = model.Price;
+            OrderID = model.OrderID;
         }
         public ConsignmentViewModel GetViewModel => new()
         {

ComputerStoreDatabaseImplement/Models/Request.cs

@@ -19,8 +19,7 @@ namespace ComputerStoreDatabaseImplement.Models
     {
         public int ID { get; private set; }
 
-        [Required]
-        public int OrderID { get; private set; }
+        public int? OrderID { get; private set; }
         public virtual Order Order { get; set; }
 
         public int? PCID { get; private set; }
@@ -61,6 +60,7 @@ namespace ComputerStoreDatabaseImplement.Models
             }
             Price = model.Price;
             PCID = model.PCID;
+            OrderID = model.OrderID;
             RequestComponents = model.RequestComponents;
         }