diff --git a/Dapper/SqlMapper.cs b/Dapper/SqlMapper.cs
index 3418c8e71e3112896ffb80478e336a7978b1cc34..92c265bb116974451ab33a992a4becea01ade31d 100644
--- a/Dapper/SqlMapper.cs
+++ b/Dapper/SqlMapper.cs
@@ -1236,6 +1236,7 @@ internal int AddField(string name)
                 if (fieldNameLookup.ContainsKey(name)) throw new InvalidOperationException("Field already exists: " + name);
                 int oldLen = fieldNames.Length;
                 Array.Resize(ref fieldNames, oldLen + 1); // yes, this is sub-optimal, but this is not the expected common case
+                fieldNames[oldLen] = name;
                 fieldNameLookup[name] = oldLen;
                 return oldLen;
             }
@@ -1298,6 +1299,19 @@ public override System.Dynamic.DynamicMetaObject BindGetMember(System.Dynamic.Ge
                 return callMethod;
             }
 
+            // Needed for Visual basic dynamic support
+            public override System.Dynamic.DynamicMetaObject BindInvokeMember(System.Dynamic.InvokeMemberBinder binder, System.Dynamic.DynamicMetaObject[] args)
+            {
+                var parameters = new System.Linq.Expressions.Expression[]
+                                     {
+                                         System.Linq.Expressions.Expression.Constant(binder.Name)
+                                     };
+
+                var callMethod = CallMethod(getValueMethod, parameters);
+
+                return callMethod;
+            }
+
             public override System.Dynamic.DynamicMetaObject BindSetMember(System.Dynamic.SetMemberBinder binder, System.Dynamic.DynamicMetaObject value)
             {
                 var parameters = new System.Linq.Expressions.Expression[]