Question

Let’s say I’ve got an object Customer with a couple properties (ID, FirstName, LastName). I’ve got the default constructor Customer(), but then I’ve also got a Customer(DataRow dr), since I load this object from a database and that’s a simple way to do it.

I frequently come to a point where I want to set up another constructor, Customer(int ID), for times when I want to load a Customer but I haven’t made the trip to the database yet. The simplest way to me seems to be like so:

Customer(int ID) {     DataTable dt = DataAccess.GetCustomer(ID);     if (dt.Rows.Count > 0)     {         // pass control to the DataRow constructor at this point?     }     else     {         // pass control to the default constructor at this point?     }    } 

It makes sense to reuse the code that’s already in the DataRow constructor, but I can’t figure out a way to call that and return what it gives me. Through Googling, I’ve found information about constructor overloading with the : this() syntax, but all those examples seem backwards or incompatible with what I’m trying to do.

So there’s a gap in my understanding of constructors, but I can’t seem to sort it out. What am I missing?

Answer 1

Simplest solution seems to be: construct another function that does the job you want to do and have both constructors call that function.