/// <summary>
/// Gets or sets the delegate for the specified key.
/// </summary>
public Delegate?this[object key]
{
get
{
ListEntry?e = null;
if (_parent == null || _parent.CanRaiseEventsInternal)
{
e = Find(key);
}
return(e?._handler);
}
set
{
ListEntry?e = Find(key);
if (e != null)
{
e._handler = value;
}
else
{
_head = new ListEntry(key, value, _head);
}
}
}
public void RemoveHandler(object key, Delegate?value)
{
ListEntry?e = Find(key);
if (e != null)
{
e._handler = Delegate.Remove(e._handler, value);
}
}
public void AddHandlers(EventHandlerList listToAddFrom)
{
ArgumentNullException.ThrowIfNull(listToAddFrom);
ListEntry?currentListEntry = listToAddFrom._head;
while (currentListEntry != null)
{
AddHandler(currentListEntry._key, currentListEntry._handler);
currentListEntry = currentListEntry._next;
}
}
public void AddHandler(object key, Delegate?value)
{
ListEntry?e = Find(key);
if (e != null)
{
e._handler = Delegate.Combine(e._handler, value);
}
else
{
_head = new ListEntry(key, value, _head);
}
}
private ListEntry?Find(object key)
{
ListEntry?found = _head;
while (found != null)
{
if (found._key == key)
{
break;
}
found = found._next;
}
return(found);
}
public void AddHandlers(EventHandlerList listToAddFrom)
{
if (listToAddFrom == null)
{
throw new ArgumentNullException(nameof(listToAddFrom));
}
ListEntry?currentListEntry = listToAddFrom._head;
while (currentListEntry != null)
{
AddHandler(currentListEntry._key, currentListEntry._handler);
currentListEntry = currentListEntry._next;
}
}
public void Dispose() => _head = null;
public ListEntry(object key, Delegate?handler, ListEntry?next)
{
_next = next;
_key = key;
_handler = handler;
}