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──Microsoft Foundation Classes──────────────────────────────────────────────
 
  Description
 
  The CObList class supports ordered lists of nonunique CObject pointers
  accessible sequentially or by pointer value. CObList lists behave like
  doubly linked lists.
 
  A variable of type POSITION is a kind of key for the list. You can use a
  POSITION variable as an iterator to sequentially traverse a list and as
  a bookmark to hold a place. A position is not the same as an index,
  however.
 
  Element insertion is very fast at the list head, at the tail, and at a
  known POSITION. A sequential search is necessary in order to look up an
  element by value or index. This search can be slow if the list is long.
 
  CObList incorporates the IMPLEMENT_SERIAL macro to support serialization
  and dumping of its elements. If a list of CObject pointers is stored to
  an archive, either with the overloaded insertion operator or with the
  Serialize member function, each CObject element is, in turn,
  serialized.
 
  If you need a dump of individual CObject elements in the list, you must
  set the depth of the dump context to 1 or greater.
 
  When a CObList object is deleted, or when its elements are removed, only
  the CObject pointers are removed, not the objects they reference.
 
  #include <afxcoll.h>
 
  See Also
 
  ◄CStringList►, ◄CPtrList►
 
  Derivation
 
  The tutorial in the <Class Library User's Guide> illustrates the
  derivation of a CPersonList class from CObList. This new list class,
  designed to hold pointers to CPerson objects, adds a new data member and
  new member functions. Note that the resulting list is not strictly "type
  safe" because it allows insertion of any CObject pointer.
 
  NOTE: You must use the IMPLEMENT_SERIAL macro in the implementation of
        your derived class if you intend to serialize the list.
 
  Public Members
 
  Construction/Destruction
 
  ◄CObList►   Constructs an empty list for CObject pointers.
 
  ◄~CObList►   Destroys a CObList object.
 
  Head/Tail Access
 
  ◄GetHead►   Returns the head element of the list (cannot be empty).
 
  ◄GetTail►   Returns the tail element of the list (cannot be empty).
 
  Operations
 
  ◄RemoveHead►   Removes the element from the head of the list.
 
  ◄RemoveTail►   Removes the element from the tail of the list.
 
  ◄AddHead►      Adds an element (or all the elements in another list) to
                 the head of the list (makes a new head).
 
  ◄AddTail►      Adds an element (or all the elements in another list) to
                 the tail of the list (makes a new tail).
 
  ◄RemoveAll►    Removes all the elements from this list.
 
  Iteration
 
  ◄GetHeadPosition►   Returns the position of the head element of the
                      list.
 
  ◄GetTailPosition►   Returns the position of the tail element of the
                      list.
 
  ◄GetNext►           Gets the next element for iterating.
 
  ◄GetPrev►           Gets the previous element for iterating.
 
  Retrieval/Modification
 
  ◄GetAt►      Gets the element at a given position.
 
  ◄SetAt►      Sets the element at a given position.
 
  ◄RemoveAt►   Removes an element from this list, specified by position.
 
  Insertion
 
  ◄InsertBefore►   Inserts a new element before a given position.
 
  ◄InsertAfter►    Inserts a new element after a given position.
 
  Searching
 
  ◄Find►        Gets the position of an element specified by pointer
                value.
 
  ◄FindIndex►   Gets the position of an element specified by a zero-based
                index.
 
  Status
 
  ◄GetCount►   Returns the number of elements in this list.
 
  ◄IsEmpty►    Tests for the empty list condition (no elements).
 
 
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