Cast an object into an object from a derived class

Question

I have a class Record that works fine:

public class Record 
{
    protected string table;
    protected string idcolumn;
    public Record(string _t         


        

Answer 1

If you get an InvalidCastException then theRecord is not an Order and you can't cast it. You could only cast it if it were created as an Order or a subclass of Order.

My guess is that whatever fetches the data from the database creates a Record when it could create an Order (and return it as a Record). Something like:

public Record Fetch(int id)
{
   // ... get data from db

   Record rec;
   if(data.Type = "Order")
      rec = new Order();
   else
      rec = new Record();

   return rec;
}