C# anticelebrities – Part 1 – The ?? operator
I decided to start a new series of posts on the anticelebrities operators / keywords of C#, being anticelebrity for a keyword / operator means that it’s not widely used by programmers. Some may say that main purpose of the members in the anticelebrity club is to be used in tricky interview questions, I hope that I will give them a push towards celebritness by explaining how to use them, at the worst case you will have some geek trivia questions for your next coffee break.
The ?? operator is a fairly simple one, it used as a shorten if condition when assigning a value into variables, checking if the object being assigned into the variable points to a NULL reference, giving it a different value in case it is NULL, or the intended value if it isn’t NULL.
The following example will make things clearer:
static void Main(string[] args)
{
string sampleText = null;
string outputText;
outputText = sampleText ?? "sampleText used to be null";
/*
* This is eqvivalent to one of the following:
* 1: if (outputText == null)
{
outputText = "sampleText used to be null";
}
else
{
outputText = sampleText
}
* 2: outputText = sampleText == null ? "sampleText used to be null" : sampleText;
*/
Console.WriteLine(outputText);
sampleText = "sampleText now has a value";
outputText = sampleText ?? "sampleText used to be null";
Console.WriteLine(outputText);
Console.Read();
}
The output will be:
More anticelebrities coming soon… stay tuned.