- 객체 정렬하기
[sourcecode language="ObjC"]
NSSortDescriptor *category1Descriptor = [[NSSortDescriptor alloc] initWithKey:@"category1" ascending:YES];
NSSortDescriptor *category2Descriptor = [[NSSortDescriptor alloc] initWithKey:@"category2" ascending:YES];
[_productList sortUsingDescriptors:[NSArray arrayWithObjects:category1Descriptor, category2Descriptor, nil]];
[category1Descriptor release];
[category2Descriptor release];
[/sourcecode]