IOS Note - Core NS Data Types
NSString (Immutable)
NSMutableString (rarely used)
NSNumber
NSValue
NSData (bits)
NSDate
NSArray (Immutable)
- once you create the array, you cannot add or remove objects
eg:
NSArray *primaryColors = [NSArray arayWithObjects:@"red", @"yellow", @"blue", nil];
NSMutableArray
NSDictionary
NSDictionary *base = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNUmber numberWithInt:2], @"binary",
[NSNUmber numberWIthInt:16], #hexadecimal", nil];
- (int)count;
- (id)objectForKey:(id)key;
- (NSArray *)allKeys;
- (NSArray *)allValues;
NSMutableDictionary
NSSet
NSMutableSet
NSOrderedSet
NSMutableOrderedSet
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Enumeration
NSArray
NSArray *myArray = ...; for (NSString *str in myArray) { if ([str isKindOfClass:[NSString class]]) { double value = [str doubleValue]; } }
NSSet
NSSet *mySet = ...; for (id obj in mySet) { if ([obj isKindOfClass:[NSString class]]) { // send NSString messages to obj } }
NSDictionary
NSDictionary *myDict = ...; for (id key in myDict) { id value = [myDict objectForKey:key]; }
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