public override string ToString()
{
StringBuilder output = new StringBuilder();
if (this.First != null)
{
DoublyLinkedListNode <T> currentElement = this.First;
while (currentElement != null)
{
output.Append(currentElement.Value + " ");
currentElement = currentElement.Next;
}
}
return(output.ToString());
}
public void AddLast(T value)
{
DoublyLinkedListNode <T> elementToAdd = new DoublyLinkedListNode <T>(value);
if (this.Last != null)
{
DoublyLinkedListNode <T> previousLastElement = this.Last;
this.Last.Next = elementToAdd;
this.Last = previousLastElement.Next;
this.Last.Prev = previousLastElement;
}
else
{
this.Last = elementToAdd;
this.First = this.Last;
}
this.Count++;
}
public DoublyLinkedListNode <T> Find(T value)
{
if (this.First != null)
{
DoublyLinkedListNode <T> currentElement = this.First;
while (currentElement != null)
{
if (currentElement.Value.CompareTo(value) == 0)
{
return(currentElement);
}
currentElement = currentElement.Next;
}
return(null);
}
throw new InvalidOperationException("Cannot search in empty linked list.");
}
public void AddAfter(T elementToAddAfter, T value)
{
DoublyLinkedListNode <T> elementToAdd = new DoublyLinkedListNode <T>(value);
if (this.First != null)
{
DoublyLinkedListNode <T> currentElement = this.First;
while (currentElement != null)
{
if (currentElement.Value.CompareTo(elementToAddAfter) == 0)
{
DoublyLinkedListNode <T> addBefore = currentElement.Next;
currentElement.Next = elementToAdd;
elementToAdd.Prev = currentElement;
elementToAdd.Next = addBefore;
if (addBefore != null)
{
addBefore.Prev = elementToAdd;
}
this.Count++;
return;
}
currentElement = currentElement.Next;
}
throw new ArgumentException($"There is no such element as: {elementToAddAfter}");
}
else
{
throw new ArgumentException("Cannot add after in empty linked list.");
}
}
public DoublyLinkedListNode(T value)
{
this.Value = value;
this.Next = null;
this.Prev = null;
}
public DoublyLinkedList(T value)
{
this.First = new DoublyLinkedListNode <T>(value);
this.Last = this.First;
this.Count = 1;
}
public DoublyLinkedList()
{
this.First = null;
this.Last = null;
this.Count = 0;
}
public void Clear()
{
this.First = null;
this.Last = null;
this.Count = 0;
}