Objective-C Foundation Framework

The Foundation framework defines a base layer of Objective-C classes. The Foundation framework is designed to:

  • provide a small set of basic utility classes
  • support the Unicode strings, object persistence, and the object distribution
  • make software development simpler and easier by introducing the consistent conventions for the things like deallocation
  • provide a level of OS independence to enhance portability

Since the framework was developed by the NeXTStep, therefore it has a class prefix of "NS"

In order to avoid importing too many classes, it is all imported in #import <Foundation/Foundation.h> instead of #import <Foundation/NSString.h>

Here is the table, lists the Foundation classes based on their functionality:

Loop Type Meaning
Data storage NSArray, NSDictionary, and NSSet provide storage for Objective-C objects of any class
Dates and times The classes namely NSDate, NSTimeZone, and NSCalendar store times and dates, and represent the calendrical info. They provides methods for calculating the date and time differences. Together with NSLocale, they offers methods for displaying dates and times in many formats and for adjusting times and dates based on the location in the world
Text and strings NSCharacterSet represents various groupings of the characters that are used by the classes named NSString and NSScanner. The NSString classes represent the text strings and provides the methods for searching, combining, and comparing the strings. An NSScanner object is used to scan numbers and words from an NSString object
File handling File handling is done by the class named NSFileManager
Exception handling Exception handling is used to handle the unexpected situations in the Objective-C program, and it is offered in Objective-C with an NSException
URL loading system A set of classes and protocols, provides access to the common Internet protocol (IP)

Objective-C Online Test

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