This class is currently not fully implemented! All set methods will work, but stringForObject: will ignore the format completely. The documentation below describes what the behavior SHOULD be...

A specialization of the NSFormatter class for generating string representations of numbers ([NSNumber] and NSDecimalNumber instances) and for parsing numeric values in strings.

See the NSFormatter documentation for description of the basic methods for formatting and parsing that are available.

There are no convenience initializers or constructors for this class. Instead, to obtain an instance, call alloc init and then -setFormat: .

The basic format of a format string uses "#" signs to represent digits, and other characters to represent themselves, in a context-dependent way. Thus, for example, @"#,###.00" means to print the number ending in.00 if it has no decimal part, otherwise print two decimal places, and to print one comma if it is greater than 1000. Thus, 1000 prints as "1,000.00", and 1444555.979 prints as "1444,555.98" (see -setRoundingBehavior:).

After setting the format, you may change the thousands separator and decimal point using set methods, or by calling -setLocalizesFormat: .

You may set separate formats to be used for positive numbers, negative numbers, and zero independently.

In addition, this class supports attributed strings (see NSAttributedString ), so that you can specify font and color attributes, among others, to display aspects of a number. You can assign specific sets of attributes for positive and negative numbers, and for specific cases including 0, NaN, and nil...