Microsoft Windows CE 3.0  

CBaseList Class

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The CBaseListclass represents a list of pointers to objects. No storage management or copying is done on the objects that are pointed to.

The implementation allows for objects to be on multiple lists simultaneously and does not require support in the objects themselves; therefore, it is particularly useful for holding variable-length lists of interface pointers.

The implementation is not multithread safe. External locks are required to maintain the integrity of the list when it is accessed from more than one thread simultaneously.

The POSITIONstructure represents a position in a linked list that is actually a void pointer. A position represents a cursor on the list that can be set to identify any element. NULL is a valid value, and several operations regard NULL as the position that is "one step off the end of the list." (In an nelement list there are n+1 places to insert, and NULL is that n+1 value.) The position of an element in the list is only invalidated if that element is deleted. Move operations might indicate that what was a valid position in one list is now a valid position in a different list.

Some operations, which at first sight seem illegal, are allowed as harmless null operations (no-ops). For example, the CBaseList::RemoveHeadImember function is legal on an empty list, and it returns NULL. This allows an atomic way to test if there is an element there and, if so, to retrieve it.

Single-element operations return positions, where a non-NULL value indicates that it worked. Entire list operations return a Boolean value, where TRUE indicates success.

Protected Data Members

m_Count Number of nodes in the list.
m_pFirst Pointer to the first node in the list.
m_pLast Pointer to the last node in the list.

Member Functions

AddAfter Inserts a list of nodes after the specified node.
AddAfterI Inserts a node after the specified node.
AddBefore Inserts a list of nodes before the specified node.
AddBeforeI Inserts a node before the specified node.
AddHead Inserts a list of nodes at the front of the list.
AddHeadI Inserts a node at the front of the list.
AddTail Appends a list of nodes to the end of the list.
AddTailI Appends a node to the end of the list.
CBaseList Constructs a CBaseListobject.
FindI Returns the first position that holds the specified object.
GetCountI Returns the number of objects in the list.
GetHeadPositionI Returns a cursor identifying the first element of the list.
GetI Returns the object at the specified position.
GetNextI Returns the specified object and updates the position.
GetTailPositionI Returns a cursor identifying the last element of the list.
MoveToHead Moves the node or list of nodes to the beginning of a second list.
MoveToTail Moves the node or list of nodes to the end of a second list.
Next Returns the next position in the list.
Prev Returns the previous position in the list.
RemoveAll Removes all nodes from the list.
RemoveHeadI Removes the first node in the list.
RemoveI Removes the specified node from the list.
RemoveTailI Removes the last node in the list.
Reverse Reverses the order of the pointers to the objects in the list.