NSMutableOrderedSet to NSMutableArray

ios objective-c nsmutablearray nsorderedset nsmutableorderedset
Landon picture Landon · Oct 22, 2013 · Viewed 11.6k times · Source 
array = [NSMutableArray arrayWithArray:[set allObjects]];

This worked with an NSSet, but how do I get it to work with an NSMutableOrderedSet?

Answer

Brad Allred picture Brad Allred · Oct 22, 2013

there is a method on the NSOrderedSet class to get an array [orderedSet array]. you can then do [array mutableCopy] to get a mutable array.

or use [NSMutableArray arrayWithArray:[set array]]; if you prefer.

do be aware of this, however:

This return a proxy object for the receiving ordered set, which acts like an immutable array. While you cannot mutate the ordered set through this proxy, mutations to the original ordered set will be reflected in the proxy and it will appear to change spontaneously, since a copy of the ordered set is not being made.

basically you must copy the array if you don't want this behavior.

Related questions

How do I sort an NSMutableArray with custom objects in it?

What I want to do seems pretty simple, but I can't find any answers on the web. I have an NSMutableArray of objects, and let's say they are 'Person' objects. I want to sort the NSMutableArray by Person.birthDate which …

Read More
The best way to remove duplicate values from NSMutableArray in Objective-C?

The best way to remove duplicate values (NSString) from NSMutableArray in Objective-C? Is this the easiest and right way to do it? uniquearray = [[NSSet setWithArray:yourarray] allObjects];

Read More
'Invalid update: invalid number of rows in section 0

I've read all of the related posts regarding this and I am still having an error: 'Invalid update: invalid number of rows in section 0. The number of rows contained in an existing section after the update (5) must be equal to …

Read More