multithreading - Objective C - performSelectorInBackground V.S detachNewThreadSelector? -

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both detachnewthreadselector , performselectorinbackground used call method in background.

is there difference between 2 methods? or both work same way?

they're both same different paradigms. behind scenes same thing. real difference -[performselectorinbackground:withobject:] follows other performselector style methods in they're defined on nsobject , message defines selector wish perform.

in general, should never have call either of these methods. favor using grand central dispatch or nsoperation , nsoperationqueue factor out expensive operations on other threads. both gcd , nsoperation classes give memory management, thread pool management , many other things you'll miss using older style dispatch methods.


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