formatting - C#: Connection between IFormattable, IFormatProvider and ICustomFormatter, and when to use what

Question

What are the difference and connection between IFormattable, IFormatProvider and ICustomFormatter and when would they be used? A simple implementation example would be very nice too.

And I don't really mean when it is used in the .net framework, but when I would implement these myself and in that case what classes would typically implement what interface and how to do it properly.

question from:https://stackoverflow.com/questions/1697470/c-connection-between-iformattable-iformatprovider-and-icustomformatter-and-w