Add explicit list of supported types

SabreTools.Library/DatFiles/DatFile.cs

@@ -2339,7 +2339,6 @@ namespace SabreTools.Library.DatFiles
 
         #endregion
 
-        // TODO: See if any of the helper methods can be broken up a bit more neatly
         #region Rebuilding and Verifying
 
         /// <summary>
@@ -3777,6 +3776,15 @@ namespace SabreTools.Library.DatFiles
             return rom;
         }
 
+        /// <summary>
+        /// Get supported types for write
+        /// </summary>
+        /// <returns>List of supported types for writing</returns>
+        protected virtual ItemType[] GetSupportedTypes()
+        {
+            return Enum.GetValues(typeof(ItemType)) as ItemType[];
+        }
+
         /// <summary>
         /// Get if an item should be ignored on write
         /// </summary>
@@ -3803,6 +3811,10 @@ namespace SabreTools.Library.DatFiles
                     return true;
             }
 
+            // If we have an item type not in the list of supported values
+            if (!GetSupportedTypes().Contains(datItem.ItemType))
+                return true;
+
             return false;
         }