updated CardType and Enumeration classes (#1528)

* updated CardType and Enumeration classes

* Update per IEvangelist's suggestion

* Update src/Services/Ordering/Ordering.Domain/SeedWork/Enumeration.cs

Co-authored-by: David Pine <david.pine@microsoft.com>

Co-authored-by: Sumit Ghosh <sumit.ghosh@neudesic.com>
Co-authored-by: David Pine <david.pine@microsoft.com>

src/Services/Ordering/Ordering.Domain/AggregatesModel/BuyerAggregate/CardType.cs

@@ -9,9 +9,9 @@ namespace Microsoft.eShopOnContainers.Services.Ordering.Domain.AggregatesModel.B
     public class CardType
         : Enumeration
     {
-        public static CardType Amex = new CardType(1, "Amex");
-        public static CardType Visa = new CardType(2, "Visa");
-        public static CardType MasterCard = new CardType(3, "MasterCard");
+        public static CardType Amex = new CardType(1, nameof(Amex));
+        public static CardType Visa = new CardType(2, nameof(Visa));
+        public static CardType MasterCard = new CardType(3, nameof(MasterCard));
 
         public CardType(int id, string name)
             : base(id, name)

src/Services/Ordering/Ordering.Domain/SeedWork/Enumeration.cs

@@ -11,27 +11,23 @@ namespace Microsoft.eShopOnContainers.Services.Ordering.Domain.SeedWork
 
         public int Id { get; private set; }
 
-        protected Enumeration(int id, string name)
-        {
-            Id = id;
-            Name = name;
-        }
+        protected Enumeration(int id, string name) => (Id, Name) = (id, name);
 
         public override string ToString() => Name;
-
-        public static IEnumerable<T> GetAll<T>() where T : Enumeration
-        {
-            var fields = typeof(T).GetFields(BindingFlags.Public | BindingFlags.Static | BindingFlags.DeclaredOnly);
-
-            return fields.Select(f => f.GetValue(null)).Cast<T>();
-        }
-
+        
+        public static IEnumerable<T> GetAll<T>() where T : Enumeration =>
+            typeof(T).GetFields(BindingFlags.Public |
+                                BindingFlags.Static |
+                                BindingFlags.DeclaredOnly)
+                     .Select(f => f.GetValue(null))
+                     .Cast<T>();
+        
         public override bool Equals(object obj)
         {
-            var otherValue = obj as Enumeration;
-
-            if (otherValue == null)
+            if (obj is not Enumeration otherValue)
+            {
                 return false;
+            }
 
             var typeMatches = GetType().Equals(obj.GetType());
             var valueMatches = Id.Equals(otherValue.Id);