What is “category” in Objective-C?

iphone objective-c ios categories
wOlVeRiNe picture wOlVeRiNe · Sep 14, 2011 · Viewed 24k times · Source

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How does a category work in Objective-C?

I am just getting started with Objective-C and was wondering when and where am i supposed to use category in objective C. is it a class or a protocol? An explanatory example would be of great help. Thanks

Answer

Jhaliya picture Jhaliya · Sep 14, 2011

A category allows you to add methods to an existing class—even to one for which you do not have the source.

Categories are a powerful feature that allows you to extend the functionality of existing classes without subclassing

Check the apple doc for the Category in Objective-C

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