Add payloadData and expiration to the TokenExpiredException exception

src/JWT/JWT.cs

@@ -264,7 +264,11 @@ public static void Verify(string payloadJson, string decodedCrypto, string decod
             var secondsSinceEpoch = Math.Round((DateTime.UtcNow - UnixEpoch).TotalSeconds);
             if (secondsSinceEpoch >= expInt)
             {
-                throw new TokenExpiredException("Token has expired.");
+                throw new TokenExpiredException("Token has expired.")
+                {
+                    Expiration = UnixEpoch.AddSeconds(expInt),
+                    PayloadData = payloadData
+                };
             }
         }
 

src/JWT/TokenExpiredException.cs

@@ -1,12 +1,35 @@
 using System;
+using System.Collections.Generic;
 
 namespace JWT
 {
     public class TokenExpiredException : Exception
     {
+        private const string PayloadDataKey = "PayloadData";
+        private const string ExpirationKey = "Expiration";
+
         public TokenExpiredException(string message)
-            : base(message)
+             : base(message)
+        {
+        }
+
+        public Dictionary<string, object> PayloadData
+        {
+            get { return GetOrDefault<Dictionary<string, object>>(PayloadDataKey); }
+            internal set { Data.Add(PayloadDataKey, value); }
+        }
+
+        public DateTime? Expiration
+        {
+            get { return GetOrDefault<DateTime?>(ExpirationKey); }
+            internal set { Data.Add(ExpirationKey, value); }
+        }
+
+        private T GetOrDefault<T>(string key)
         {
+            if (Data.Contains(key))
+                return (T)Data[key];
+            return default(T);
         }
     }
 }