Name
NSEnumerator — Mac OS X 10.0
Synopsis
This
class enumerates the contents of a
collection. Instances of this class are created by the collection
classes, generally with the method
objectEnumerator
. NSArray
declares the method reverseObjectEnumerator
, and
NSDictionary
declares
keyEnumerator
as additional methods that create
instances of NSEnumerator
.
To obtain the next object in an enumerator, we invoke the method
nextObject
. This will return an object, and
advance the enumerator position forward in the collection. When the
enumerator has exhausted the collection,
nextObject
returns nil
.
Enumerators cannot be reset; once you have enumerated a collection,
you must obtain an new enumerator from the collection to start again.
The method allObjects
is used to return an
NSArray
of the objects that have not yet been
enumerated. See Chapter 2 for more information on
collections and enumerators.
|
@interface NSEnumerator : NSObject
|
// Instance Methods
|
- (NSArray *)allObjects;
|
- (id)nextObject;
|
Subclasses
NSDirectoryEnumerator
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