CObList::RemoveAt
Removes the specified element from this list.
void RemoveAt(
POSITION position
);
Параметры
- position
The position of the element to be removed from the list.
Заметки
When you remove an element from a CObList, you remove the object pointer from the list. It is your responsibility to delete the objects themselves.
You must ensure that your POSITION value represents a valid position in the list. If it is invalid, then the Debug version of the Microsoft Foundation Class Library asserts.
The following table shows other member functions that are similar to CObList::RemoveAt.
Class |
Member Function |
|---|---|
void RemoveAt( POSITION position ); |
|
void RemoveAt( POSITION position ); |
Пример
Be careful when removing an element during a list iteration. The following example shows a removal technique that guarantees a valid POSITION value for GetNext.
See CObList::CObList for a listing of the CAge class.
CObList list;
POSITION pos1, pos2;
CObject* pa;
list.AddHead(new CAge(21));
list.AddHead(new CAge(40));
list.AddHead(new CAge(65)); // List now contains (65 40, 21).
for (pos1 = list.GetHeadPosition(); (pos2 = pos1) != NULL;)
{
if (*(CAge*) list.GetNext(pos1) == CAge(40))
{
pa = list.GetAt(pos2); // Save the old pointer for
//deletion.
list.RemoveAt(pos2);
delete pa; // Deletion avoids memory leak.
}
}
#ifdef _DEBUG
afxDump.SetDepth(1);
afxDump << _T("RemoveAt example: ") << &list << _T("\n");
#endif
The results from this program are as follows:
RemoveAt example: A CObList with 2 elements
a CAge at $4C1E 65
a CAge at $4B22 21
Требования
Header: afxcoll.h