TcmUri constructor does not take null as argument

Question

We are busy upgrading 2009 to 2011 and found an annoying difference between the TOM.Net API for both versions. If you try to create a TcmUri object with the single-argument constructor, and the value of the argument is null, the behavior is different:

// 2009
TcmUri uri = new TcmUri(null);
log.Debug("found uri " + uri.ToString());
// the log shows 'found uri tcm:0-0-0'


// 2011
TcmUri uri = new TcmUri(null);
// the code breaks here with exception 'Null is not allowed'
log.Debug("found uri " + uri.ToString());

Of course, we don't pass 'null' on purpose. But we have many situations where we configure a uri through a package variable. When the variable isn't in the package, we end up with the null value.

Did anyone encounter the same problem? If so, how did you solve it?

Answer 1

I thought the argument was always required. I guess it didn't always validate it correctly.

Anyway, you could check for null or TcmUri.IsValid before trying to parse it and use a default value of TcmUri.UriNull if you want it to work the same as before. That does require code changes but I don't see any way around that.

Answer 2

To handle all types of TcmUri issues, we have our own TcmUri class which handles

• NullUri's
• Implicit Operators

You can view @Rob code at TcmUri.cs.