Summary

This chapter covered some of the most commonly used Foundation classes: NSString, NSArray, NSDictionary, NSSet, NSNumber, NSData, and NSURL. NSString and NSArray are safer than their plain C analogs because they are bounds checked. The NSDictionary class implements associative arrays similar to those found in other languages. The NSNumber class provides a wrapper for numeric values so that numbers can be treated as objects when necessary. NSData provides similar wrapping services for blocks of bytes. The last section of the chapter examined some Foundation entities that are plain C structures: NSRange, NSPoint, NSSize, and NSRect.