Reusable NSMutableDictionary
Someone in that forum proposed me a code solution that worked great, but for my understanding, I would like to know what is the difference 开发者_如何学运维between the 2 blocks of code:
Block 1
NSMutableDictionary* step_info = [NSMutableDictionary dictionary];
Block 2
NSMutableDictionary* step_info = nil;
step_info = [NSMutableDictionary dictionary];
It is may be also important to mention that step_info has to be filled and reuse repeatedly to load into another NSmutabledictionary.
Thank's for your help
None. The compiler optimises step_info = nil
away and you're left with the exact same code.
The following is another approach you could take:
NSMutableDictionary *step_info;
step_info = [NSMutableDictionary dictionary];
Having NSMutableDictionary* step_info;
first allows you to use step_info = [NSMutableDictionary dictionary]
later in the same block of code.
If you wish to assign a value to step_info in multiple methods, it'd be better if you add NSMutableDictionary* step_info
in the @interface
section of the header file.
That way you can use step_info = [[NSMutableDictionary alloc] init]
in any method in your implementation file, then assign values and keys this way: [step_info setValue: value forKey: key];
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