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iOS Objective-C Basics (Retired) Foundation Framework NSDictionary

Bonbon Lang-es
PLUS
Bonbon Lang-es
Courses Plus Student 2,040 Points
Posted by Bonbon Lang-es
Bonbon Lang-es
Courses Plus Student 2,040 Points

When to use alloc/init in NSMutableDictionary

I noticed Doug declared NSMutableDictionary as 

NSMutableDictionary *mutableBook = [NSMutableDictionary dictionaryWithDictionary:book];

instead of 

NSMutableDictionary *mutableBook = [[NSMutableDictionary alloc] initWithDictionary:book];

When is the right time to use the first one, and the second one?

1 Answer

Vittorio Somaschini
Vittorio Somaschini
33,371 Points
Vittorio Somaschini
Vittorio Somaschini
33,371 Points

Hello !

They should be the same.

The first way is quicker, but for example, when you want to just create a dictionary without assign values to it you can you the second way you have listed.