added missing logic

Catamaran/Catamaran/CollectionGenericObjects/ArrayGenericObjects.cs

@@ -38,7 +38,11 @@ namespace Catamaran.CollectionGenericObjects
 
         public T? Get(int position)
         {
-            return _collection[position];
+            if (position >= 0 && position < Count)
+            {
+                return _collection[position];
+            }
+            return null;
         }
 
         public int Insert(T obj)