Updated Doubly linked list to allow for the combining of 2 lists

C#/Datastructures/DoublyLinkedList.cs

@@ -28,6 +28,30 @@ namespace C_.Datastructures
             };
         }
 
+
+        public static DoublyLinkedList<T> Create(DoublyLinkedList<T> list1, DoublyLinkedList<T> list2)
+        {
+            //Create a new list from 2 separate lists
+            
+            DoublyLinkedList<T> list;
+
+            list = list1;
+            if (list == null || list.Count == 0) return list2;
+
+            //Find end of list and append fist item of next list
+            if (list2 == null || list.Count == 0) return list;
+
+            DoublyLinkedListNode<T>? end = list.Traverse();
+
+            //Connect up pointers at ajoining section
+            end!.Next = list2!.Head;
+            end!.Next!.Prev = end;
+            end = list2.Tail;
+            list.Count += list2!.Count;
+
+            return list;
+        }
+
         public T? this[int i]
         {
             get

C#/Program.cs

@@ -16,6 +16,19 @@ list.Add(6);
 list.Add(7);
 list.Add(8);
 
+DoublyLinkedList<int> list2 = new DoublyLinkedList<int>();
+
+list2.Add(1);
+list2.Add(2);
+list2.Add(3);
+list2.Add(4);
+list2.Add(5);
+list2.Add(6);
+list2.Add(7);
+list2.Add(8);
+
+var list3 = DoublyLinkedList<int>.Create(list, null);
+
 var x = list[-6];
 
 Console.WriteLine(x);