Replacing key/value in NSDictionary

Question

If I have a dictionary with the following key/value "foo"/"bar" and declared [dictionary setObject:@"baz" forKey:@"foo"]; would this replace the current key value pair with "foo"/"baz" and delete "foo"/"bar"?

Answer 1

The behave of an NSMutableDictionary (as any common hash table) is that if it does not exists it creates a new key/value pair, if it already exits it will replace the existing value with the new one.

Answer 2

The documentation here;

http://developer.apple.com/library/mac/#documentation/Cocoa/Reference/Foundation/Classes/NSMutableDictionary_Class/Reference/Reference.html%23//apple_ref/doc/uid/TP40003692

suggests that it would. But please, don't take my word for it, read them yourself.

Perhaps you should also read;

http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/Collections/Collections.html%23//apple_ref/doc/uid/10000034i