Getting unique items from NSMutableArray

Posted by Gidogeek on Stack Overflow See other posts from Stack Overflow or by Gidogeek
Published on 2010-06-03T20:03:12Z Indexed on 2010/06/03 20:04 UTC
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Filed under:

objective-c

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query

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nsmutablearray

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nsarray

Hi Guys,

I have a question about Objective-C today involving NSMutableArray. Coming from a .net/c# background I'm having some trouble working with these things.

Let's say I have an object called "Song"

My song has 3 properties:

Title
Artist
Genre

I have a NSMutableArray or NSArray wich holds all my Song objects.

How would I go about trying to 'query' my array to get a new array with only (Unique) Artists or Genre's.

Where as in .net you would write a simple LINQ query with a DISTINCT clause, how would one solve this in Objective-C ? I'm guessing with predicates but am struggling to find a solution.

Thanks in advance.

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