How to sort a NSArray alphabetically?

The other answers provided here mention using @selector(localizedCaseInsensitiveCompare:) This works great for an array of NSString, however if you want to extend this to another type of object, and sort those objects according to a 'name' property, you should do this instead:

NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES];
sortedArray=[anArray sortedArrayUsingDescriptors:@[sort]];

Your objects will be sorted according to the name property of those objects.

If you want the sorting to be case insensitive, you would need to set the descriptor like this

NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES selector:@selector(caseInsensitiveCompare:)];

The simplest approach is, to provide a sort selector (Apple's documentation for details)

Objective-C

sortedArray = [anArray sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];

Swift

let descriptor: NSSortDescriptor = NSSortDescriptor(key: "YourKey", ascending: true, selector: "localizedCaseInsensitiveCompare:")
let sortedResults: NSArray = temparray.sortedArrayUsingDescriptors([descriptor])

---

Apple provides several selectors for alphabetic sorting:

• compare:
• caseInsensitiveCompare:
• localizedCompare:
• localizedCaseInsensitiveCompare:
• localizedStandardCompare:

Swift

var students = ["Kofi", "Abena", "Peter", "Kweku", "Akosua"]
students.sort()
print(students)
// Prints "["Abena", "Akosua", "Kofi", "Kweku", "Peter"]"

Reference

Another easy method to sort an array of strings consists by using the NSString description property this way:

NSSortDescriptor *valueDescriptor = [NSSortDescriptor sortDescriptorWithKey:@"description" ascending:YES];
arrayOfSortedStrings = [arrayOfNotSortedStrings sortedArrayUsingDescriptors:@[valueDescriptor]];

A more powerful way of sorting a list of NSString to use things like NSNumericSearch :

NSArray *sortedArrayOfString = [arrayOfString sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
            return [(NSString *)obj1 compare:(NSString *)obj2 options:NSNumericSearch];
        }];

Combined with SortDescriptor, that would give something like :

NSSortDescriptor *sort = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES comparator:^NSComparisonResult(id obj1, id obj2) {
        return [(NSString *)obj1 compare:(NSString *)obj2 options:NSNumericSearch];
    }];
NSArray *sortedArray = [anArray sortedArrayUsingDescriptors:[NSArray arrayWithObject:sort]];