CODEWITHSUNDEEP
objective-cnsmutabledictionary
djt9000
djt9000

Reputation: 367

NSMutable Dictionary adding objects

Is there a more efficient way to add objects to an NSMutable Dictionary than simple iteration?

Example:

// Create the dictionary

NSMutableDictionary *myMutableDictionary = [NSMutableDictionary dictionary];    

// Add the entries

[myMutableDictionary setObject:@"Stack Overflow" forKey:@"http://stackoverflow.com"];
[myMutableDictionary setObject:@"SlashDotOrg" forKey:@"http://www.slashdot.org"];
[myMutableDictionary setObject:@"Oracle" forKey:@"http://www.oracle.com"];

Just curious, I'm sure that this is the way it has to be done.

Upvotes: 28

Views: 77455

Answers (4)

Jeremiah Radich
Jeremiah Radich

Reputation: 1

NSMutableDictionary *example = [[NSMutableDictionary alloc]initWithObjectsAndKeys:@5,@"burgers",@3, @"milkShakes",nil];

The objects come before the keys.

Upvotes: 0

Tiago Almeida
Tiago Almeida

Reputation: 14237

Allow me to add some information to people that are starting.

It is possible to create a NSDictionary with a more friendly syntax with objective-c literals:

NSDictionary *dict = @{ 
    key1 : object1, 
    key2 : object2, 
    key3 : object3 };

Upvotes: 8

stefanB
stefanB

Reputation: 79930

If you have all the objects and keys beforehand you can initialize it using NSDictionary's:

dictionaryWithObjects:forKeys:

Of course this will give you immutable dictionary not mutable. It depends on your usage which one you need, you can get a mutable copy from NSDictionary but it seems easier just to use your original code in that case: 

NSDictionary * dic = [NSDictionary dictionaryWith....];
NSMutableDictionary * md = [dic mutableCopy];
... use md ...
[md release];

Upvotes: 15

Andrew Johnson
Andrew Johnson

Reputation: 13286

NSDictionary *entry = [NSDictionary dictionaryWithObjectsAndKeys:
  [NSNumber numberWithDouble:acceleration.x], @"x",
  [NSNumber numberWithDouble:acceleration.y], @"y",
  [NSNumber numberWithDouble:acceleration.z], @"z",
  [NSDate date], @"date", 
  nil];

Upvotes: 20

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