Unai Zorrilla Castro 4ef6b63913 Review on 17/04/2017
2017-04-17 12:28:12 +02:00

104 lines
2.9 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
namespace Microsoft.eShopOnContainers.Services.Ordering.Domain.SeedWork
{
public abstract class Enumeration : IComparable
{
public string Name { get; private set; }
public int Id { get; private set; }
protected Enumeration()
{
}
protected Enumeration(int id, string name)
{
Id = id;
Name = name;
}
public override string ToString()
{
return Name;
}
public static IEnumerable<T> GetAll<T>() where T : Enumeration, new()
{
var type = typeof(T);
var fields = type.GetTypeInfo().GetFields(BindingFlags.Public | BindingFlags.Static | BindingFlags.DeclaredOnly);
foreach (var info in fields)
{
var instance = new T();
var locatedValue = info.GetValue(instance) as T;
if (locatedValue != null)
{
yield return locatedValue;
}
}
}
public override bool Equals(object obj)
{
var otherValue = obj as Enumeration;
if (otherValue == null)
{
return false;
}
var typeMatches = GetType().Equals(obj.GetType());
var valueMatches = Id.Equals(otherValue.Id);
return typeMatches && valueMatches;
}
public override int GetHashCode()
{
return Id.GetHashCode();
}
public static int AbsoluteDifference(Enumeration firstValue, Enumeration secondValue)
{
var absoluteDifference = Math.Abs(firstValue.Id - secondValue.Id);
return absoluteDifference;
}
public static T FromValue<T>(int value) where T : Enumeration, new()
{
var matchingItem = Parse<T, int>(value, "value", item => item.Id == value);
return matchingItem;
}
public static T FromDisplayName<T>(string displayName) where T : Enumeration, new()
{
var matchingItem = Parse<T, string>(displayName, "display name", item => item.Name == displayName);
return matchingItem;
}
private static T Parse<T, K>(K value, string description, Func<T, bool> predicate) where T : Enumeration, new()
{
var matchingItem = GetAll<T>().FirstOrDefault(predicate);
if (matchingItem == null)
{
var message = string.Format("'{0}' is not a valid {1} in {2}", value, description, typeof(T));
throw new InvalidOperationException(message);
}
return matchingItem;
}
public int CompareTo(object other)
{
return Id.CompareTo(((Enumeration)other).Id);
}
}
}