private IMultiLinkedList <TItem> EnsureList(TGroup group, bool createIfNecessary)
{
if (!_dictionary.ContainsKey(group))
{
if (createIfNecessary)
{
var list = new MultiLinkedList <TItem>();
_dictionary[group] = list;
if (_lists.Count > 0)
{
// Attach the list to our list chain
var previous = _lists[_lists.Count - 1];
previous.SetNext(list);
list.SetPrevious(previous);
}
_lists.Add(list);
return(list);
}
}
else
{
return(_dictionary[group]);
}
return(null);
}
private IMultiLinkedList <TItem> EnsureList(TGroup group)
{
if (group == null)
{
return(null);
}
if (_dictionary.ContainsKey(group))
{
return(_dictionary[group]);
}
var list = new MultiLinkedList <TItem>();
_dictionary[group] = list;
_lists.Add(list);
return(list);
}