NSDictionary

http://developer.apple.com/documentation/Cocoa/Reference/Foundation/Classes/NSDictionary_Class/Reference/Reference.html

See FoundationCollections for a general overview; see DesignDictionary for a critique of the dictionary design in general.

Here's a little example I threw together to use NSDictionary with some strings. It's not particularly good, but it might help you understand a little better.

#import <Cocoa/Cocoa.h>

int main(int argc, const char *argv[])
{
    NSDictionary *dict;
    NSEnumerator *enumerator;
    id key;
    NSAutoreleasePool * pool = [[NSAutoreleasePool alloc] init];
    
    dict = [NSDictionary dictionaryWithObjectsAndKeys:
                   @"A beverage prepared by heating cocoa with water/milk",
                   @"cocoa", 
                   @"http://www.cocoadev.com/",
                   @"cocoadev", 
                   @"4 : a list (as of items of data or words) stored in a                         computer for reference (as for information retrieval                         or word processing)",
                   @"dictionary",
                   nil];
    
    // printf("entry for cocoa: %s\n\n",
    //        [[dict objectForKey:@"cocoa"]cString]);
    // Use of the cString method is discouraged ASCII is out Unicode is in.
    // Also watch out for [[dict objectForKey:@"cocoa"]cString] notice the
    // lack of a space between the receiver and the message.
    // And lastly since this is a Cocoa example why not use an NSLog()
    NSLog(@"entry for cocoa: %@", [dict objectForKey:@"cocoa"]);

    enumerator = [dict keyEnumerator];
    
    while ((key = [enumerator nextObject])) {
        //printf("%s : %s\n", [key cString],
        //        [[dict objectForKey: key] cString]);
        NSLog(@"%@ : %@", key, [dict objectForKey:key]);
    }
    
   [pool release];

    return 0;//NSApplicationMain(argc, argv);
}