I need to implement multiple categories for articles. I followed the recommendation of adding a ParentCategoryID to the db using the int field type. I have changed the Category.cs, CategoryDetails.cs, and ArticlesProvider.cs files as needed and sucessfully built the solution. Upon running the site I receive the System.InvalidCastException detailed below;
 

Line 78:         protected virtual CategoryDetails GetCategoryFromReader(IDataReader reader)
Line 79:         {
Line 80:             return new CategoryDetails(                
Line 81:                (int)reader["CategoryID"],
Line 82:                (int)reader["ParentID"],
 

I must be overlooking something. Any help would be greatly appreciated.

Cheers