The C# Null Coalescing Operator (??)

I was looking through some code the other day and ran across something that looked remotely familiar.  It was the null coalescing (??) operator.  I had read about this operator, but never used it.  It was introduced with the .NET 2.0 Framework.

The null coalescing operator basically checks to see if a value is null and if so returns an alternate value.  Below is a simple example.

C# Code Listing

using System;

namespace CoalesceTst

{

    class Program

    {

        static void Main(string[] args)

        {

            string userName = "GabrielGray";

            string userName2 = null;

            string name = userName ?? "<no name>";

            string name2 = userName2 ?? "<no name>";

            Console.WriteLine(name);

            Console.WriteLine(name2);

        }

    }

}