CODEWITHSUNDEEP
objective-ccocoansarraynsobject
ATV
ATV

Reputation: 4496

Retrieve object from NSArray by specifying class name

The task:

Return an object from an NSArray that's instance of the class who's name is given as parameter to the function.

Right now I have this function:

+ (id)objectOfType:(NSString *)name fromArray:(NSArray *)array
{
   for (NSObject* instance in array)
   {
      if ([instance.className isEqualToString:name])
         return instance;
   }       
   return nil;
}

However, given that I can transform an array of objects into an array of class names of the objects with this simple method call on an NSArray

[array valueForKeyPath:@"className"]

shouldn't there also be a more concise way to retrieve the object with the specified class name..?

Upvotes: 0

Views: 371

Answers (1)

Avi
Avi

Reputation: 7552

Here is a concise method, using NSPredicate and array filtering.

+ (id)objectOfType:(NSString *)name fromArray:(NSArray *)array {
    return [array filteredArrayUsingPredicate:[NSPredicate predicateWithFormat:@"class == %@", NSClassFromString(name)]].lastObject;
}

Upvotes: 1

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