Attribute reflection support

AttributeSupport.cs

// 
// MIT License
// Copyright (c) 2009 Chris Stefano <[email protected]>
// https://gist.github.com/virtualstaticvoid/105255
// 
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;

public static class AttributeSupport
{
  public static T GetAttribute<T>(this object instance)
    where T : Attribute
  {
    return instance.GetType().GetAttribute<T>(/* inherit */ true);
  }

  public static T GetAttribute<T>(this ICustomAttributeProvider provider)
    where T : Attribute
  {
    return provider.GetAttribute<T>(/* inherit */ true);
  }

  public static T GetAttribute<T>(this ICustomAttributeProvider provider, bool inherit)
    where T : Attribute
  {
    var attributes = provider.GetCustomAttributes(typeof(T), inherit);
    return attributes.Length > 0 ? attributes[0] as T : null;
  }

  public static T[] GetAttributes<T>(this ICustomAttributeProvider provider)
    where T : Attribute
  {
    return provider.GetAttributes<T>(/* inherit */ true);
  }

  public static T[] GetAttributes<T>(this ICustomAttributeProvider provider, bool inherit)
    where T : Attribute
  {
    var attributes = provider.GetCustomAttributes(typeof(T), inherit);
    return attributes.Select(attr => attr as T).ToArray();
  }

  public static void ForAttributesOf<T>(this ICustomAttributeProvider provider, Action<T> action)
    where T : Attribute
  {
    provider.ForAttributesOf<T>(/* inherit */ true, action);
  }

  public static void ForAttributesOf<T>(this ICustomAttributeProvider provider, bool inherit, Action<T> action)
    where T : Attribute
  {
    foreach (T attribute in provider.GetCustomAttributes(typeof(T), inherit))
    {
      action(attribute);
    }
  }
}