.NET Tips and Tricks

Blog archive

Adding Your Own Explicit Type Conversions in C#

In my previous tip, I showed how to add an implicit conversion to C#. But there are two rules you should follow when defining an implicit conversion: 1) An implicit conversion should never throw an error, and 2) It should never lose information. If neither of those conditions is true, you should declare the conversion as explicit, as this code does:

public class PremiumCustomer
{
  public string CustomerId {get; set;}
  public string Name {get; set;}
  public bool CanUseCredit {get; set;}

  public static explicit operator PremiumCustomer(DeadbeatCustomer dbc)
  {
    PremiumCustomer pc = new PremiumCustomer();
    pc.CustomerId = dbc.CustomerId;
    pc.Name = dbc.Name;
    if (pc.CanUseCredit != true)
    {
      pc.CanUseCredit = dbc.CanUseCredit;
    }
    else
    {
      throw new Exception("Can't convert DeadbeatCustomers with bad credit");
    }
    return pc;
  }
}

The code to convert a DeadbeatCustomer to a PremiumCustomer would need an explicit cast and look, like this:

DeadbeatCustomer db = new DeadbeatCustomer();
PremiumCustomer pc = (PremiumCustomer) db;

Posted by Peter Vogel on 02/28/2014 at 9:28 AM


comments powered by Disqus

Featured

  • Purple Blue Nebula Graphic

    How to Compute Disorder for Machine Learning Decision Trees Using C#

    Using a decision tree classifier from a machine learning library is often awkward because it usually must be customized and library decision trees have many complex supporting functions, says resident data scientist Dr. James McCaffrey, so when he needs a decision tree classifier, he always creates one from scratch. Here's how.

  • Blazor's Future: gRPC Is Key

    Blazor guru Steve Sanderson detailed what Microsoft is thinking about the future of the revolutionary project that enables .NET-based web development using C# instead of JavaScript, explaining how gRPC is key, along with a new way of testing and a scheme for installable desktop apps.

  • Don't Do It All Yourself: Exploiting gRPC Well Known Types in .NET Core

    If you're creating business services that send dates and decimal data then you may be concerned that gRPC services don't support the relevant data types. Don't Panic! There are solutions. Here's how to use them.

  • Sign

    Microsoft Points Blazor to Native Mobile Apps

    Blazor, the red-hot Microsoft project that lets .NET developers use C# for web development instead of JavaScript, is now being pointed toward the mobile realm, targeting native iOS and Android apps.

  • Circl

    Implementing State in .NET Core gRPC Messages with oneof

    In the real world, you've been dealing with the State pattern every time you designed a set of database tables. The Protocol Buffers specification lets you do the same thing when you define the messages you send and receive from your gRPC Web Service.

.NET Insight

Sign up for our newsletter.

Terms and Privacy Policy consent

I agree to this site's Privacy Policy.

Upcoming Events