?? operator

[DarwinIT]

I found the following in code I inherited.


MainClass.Logger.LogEvent(this, new BCIDEventArgs(new BCIDEvent(BCIDDEventLevel.Info, Core.Instance.UserName, null, null, log.MessageText ?? string.Empty)
));

What is the function of ?? in log.MessageText ?? string.Empty ??

I don't find that listed in the operator section of Inside C#. Is this perhaps new to 2008?

 

[jmeckley]

string nullstring = null;
if(nullstring == null)
 return string.Empty;
return nullstring;

is the same as

string nullstring = null;
return nullstring ?? string.Empty;

Jason Meckley
Programmer
Specialty Bakers, Inc.

 

[DarwinIT]

So it would be comparable to the IsNull function in SQL Server isNull(@nullstring,'')

Thanks!!!

 

[jmeckley]

yes

Jason Meckley
Programmer
Specialty Bakers, Inc.