/// <summary>
/// Internal base method to add all elements in collection
/// </summary>
private void AddElementInternal(T item, T newItem, bool after)
{
//check elements
CheckDuplicationItem(newItem);
LinkedListNode <T> oldNode = GetExistEntry(item);
//add element after
LinkedListNode <T> newNode = new LinkedListNode <T>(newItem);
//select to add first/last + add
if (after)
{
_elementsList.AddAfter(oldNode, newNode);
}
else
{
_elementsList.AddBefore(oldNode, newNode);
}
_elementsMap.Add(newItem, newNode);
//rise event
var args = after ? NotifySetChangedEventArgs <T> .ConstructAddAfterAction(item, newItem) : NotifySetChangedEventArgs <T> .ConstructAddBeforeAction(item, newItem);
OnCollectionChanged?.Invoke(args);
}
public void Clear()
{
//clear collections
_elementsMap.Clear();
_elementsList.Clear();
//rise clear event
OnCollectionChanged?.Invoke(NotifySetChangedEventArgs <T> .ConstructClear());
}
/// <summary>
/// Try add first element to collection
/// </summary>
private bool TryAddFirstInternal(T item)
{
//check count
if (Count != 0)
{
return(false);
}
//check null item
CheckNullElement(item);
//add to collections
LinkedListNode <T> newNode = _elementsList.AddFirst(item);
_elementsMap.Add(item, newNode);
//change event
OnCollectionChanged?.Invoke(NotifySetChangedEventArgs <T> .ConstructAddFirst(item));
return(true);
}
public bool Remove(T item)
{
//check element
CheckNullElement(item);
//check exist
LinkedListNode <T> entry;
if (!_elementsMap.TryGetValue(item, out entry))
{
return(false);
}
//remove
_elementsMap.Remove(item);
_elementsList.Remove(entry.Value);
//rise change event
var args = NotifySetChangedEventArgs <T> .ConstructRemoveAction(item);
OnCollectionChanged?.Invoke(args);
return(true);
}