The NSScanner class is an Objective-C class implemented in the Foundation framework, starting from Mac OS X 10.0. The NSScanner is a highly configurable tool designed for extracting substrings and numeric values from loosely demarcated strings.
The NSScanner class is an abstract superclass of a class cluster that declares the programmatic interface for an object that scans values from an NSString object.
An NSScanner object interprets and converts the characters of an NSString object into number and string values. You assign the scanner’s string on creating it, and the scanner progresses through the characters of that string from beginning to end as you request items.
Because of the nature of class clusters, scanner objects aren’t actual instances of the NSScanner class but one of its private subclasses. Although a scanner object’s class is private, its interface is public, as declared by this abstract superclass, NSScanner. The primitive methods of NSScanner are string and all of the methods listed under Configuring a Scanner. The objects you create using this class are referred to as scanner objects (and when no confusion will result, merely as scanners).
You can set an NSScanner object to ignore a set of characters as it scans the string using the charactersToBeSkipped property. Characters in the skip set are skipped over before scanning the target. The default set of characters to skip is the whitespace and newline character set.
To retrieve the unscanned remainder of the string, use [[scanner string] substringFromIndex: [scanner scanLocation]].
