You can use predefined attributes to attach metadata to type members.
You can also define a custom attribute by creating a new class inheriting from System.Attribute. The class name must end in “Attribute”. You typically define a constructor that takes arguments that consist of the metadata that you want to attach to the type member.
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| /// <summary>/// Attach to a class method to indicate kg of methane that is/// output when calling the method./// </summary>public class MethaneFootprintAttribute : Attribute{ public double kgMethane; public MethaneFootprintAttribute(int kg) { kgMethane = kg; }} |
You can use the new attribute to attach metadata to individual type members. You use the name of the new class, without the trailing “Attribute”.
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| [MethaneFootprint(45)]public void FeedCowInBarn(){ Console.WriteLine("Cow eats slop in dim confines of barn");}[MethaneFootprint(29)]public void LetGrazeOutside(){ Console.WriteLine("Cow enjoys grazing and ends up healthier");} |