如何在asp.net中更改自动生成的cs文件

I have an autogenerated class from entity framework I have changed the type from a string to long in the database along with the name as well thereafter transformed the templates and rebuilt the project however I get an error "The 'Phase' property on 'PropertyDescription' could not be set to a 'Int64' value. You must set this property to a non-null value of type 'String'. "I have an autogenerated class from entity frame