Sort Array with comparator

For a mutable array of dictionaries:

NSMutableArray *aMutableArray = [NSMutableArray arrayWithObjects:
         [NSDictionary dictionaryWithObjectsAndKeys:
          @"A", @"name",
          [NSNumber numberWithInt:6], @"value", nil],
         [NSDictionary dictionaryWithObjectsAndKeys:
          @"C", @"name",
          [NSNumber numberWithInt:2], @"value", nil],
         [NSDictionary dictionaryWithObjectsAndKeys:
          @"B", @"name",
          [NSNumber numberWithInt:4], @"value", nil], nil];
In this case case here's how you sort it by value:


NSSortDescriptor *aSortDescriptor = [[NSSortDescriptor alloc] initWithKey:@"value" ascending:YES];
[aMutableArray sortUsingDescriptors:[NSArray arrayWithObject:aSortDescriptor]];



Otherwise:


NSSortDescriptor *lastNameDescriptor = [[NSSortDescriptor alloc] initWithKey:@"lastname" ascending:YES comparator:^(id left, id right) {

float v1 = [left floatValue];

float v2 = [right floatValue];

if (v1 < v2)

return NSOrderedAscending;

else if (v1 > v2)

return NSOrderedDescending;

else

return NSOrderedSame;

}];

[data sortUsingDescriptors:[NSArray arrayWithObject:lastNameDescriptor]];