How can I sort strings in NSMutableArray into alphabetical order?

问题

I have a list of strings in an NSMutableArray, and I want to sort them into alphabetical order before displaying them in my table view.

How can I do that?

回答1:

There is the following Apple's working example, using sortedArrayUsingSelector: and localizedCaseInsensitiveCompare: in the Collections Documentation:

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

Note that this will return a new sorted array. If you want to sort your NSMutableArray in place, then use sortUsingSelector: instead, like so:

[mutableArray sortUsingSelector:@selector(localizedCaseInsensitiveCompare:)];

回答2:

Here's an updated answer for Swift:

• Sorting can be done in Swift with the help of closures. There are two methods - sort and sorted which facilitate this.

  var unsortedArray = [ "H", "ello", "Wo", "rl", "d"]
  var sortedArray = unsortedArray.sorted { $0.localizedCaseInsensitiveCompare($1) == NSComparisonResult.OrderedAscending }
  

  Note: Here sorted will return a sorted array. The unsortedArray itself will not be sorted.

• If you want to sort unsortedArray itself, use this

  unsortedArray.sort { $0.localizedCaseInsensitiveCompare($1) == NSComparisonResult.OrderedAscending }
  

---

Reference :

• Here is the documentation for Swift's sorting methods.

• Docs for different String comparison methods here.

---

Optional:

Instead of using localizedCaseInsensitiveCompare, this could also be done:

stringArray.sort{ $0.lowercaseString < $1.lowercaseString }

or even

stringArray.sort{ $0 < $1 }

if you want a case sensitive comparison

回答3:

It's easy to get the ascending order. Follow the bellow steps,,,

Model 1 :

NSSortDescriptor *sortDesc = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES];
sortedArray=[yourArray sortedArrayUsingDescriptors:@[sortDesc]];

If you want the sorting to be case insensitive, you would need to set the descriptor like this,,
Model 2 :

NSSortDescriptor * sortDesc = [NSSortDescriptor sortDescriptorWithKey:@"name" ascending:YES selector:@selector(caseInsensitiveCompare:)]; 
sortedArray=[yourArray sortedArrayUsingDescriptors:@[sortDesc]];

回答4:

For me this worked....

areas = [areas sortedArrayUsingSelector:@selector(localizedCaseInsensitiveCompare:)];

Here areas is NSArray. I hope it helps someone.

来源：https://stackoverflow.com/questions/6315323/how-can-i-sort-strings-in-nsmutablearray-into-alphabetical-order