#472 – Attributes Can Be Attached to a Variety of Elements

Custom attributes can be attached not only to class methods, but to a number of different types of elements.

You can attach an attribute to any of the following elements:

  • An assembly
  • A class
  • A constructor
  • A delegate
  • An enumerated type
  • An event
  • A field
  • A generic parameter
  • An interface
  • A method
  • A module (.dll or .exe)
  • A parameter
  • A property
  • A return value
  • A struct

Below is an example of attaching custom attributes to parameters.

    public sealed class PopCultureAttribute : Attribute
    {
        public string Trivia;
        public object SuggestedValue;

        public PopCultureAttribute(string trivia, object suggestedValue)
        {
            Trivia = trivia;
            SuggestedValue = suggestedValue;
        }
    }

 

        public void FeedCowInBarn(
            [PopCulture("Cows stomachs can bloat when feeding them rich grains", "Silage")] string feedType,
            [PopCulture("Cows spend 6 hrs/day eating", 60)] int numMinutes)
        {
            Console.WriteLine("Cow eats slop in dim confines of barn.  {0}, {1}", feedType, numMinutes);
        }