ToString() returns null?

Question

I am trying to determine cause of 'Null reference exception' on published remote site. So, I can't debug it directly and can operate only with logs. So my question is:
Is it possible, that .ToString() method of any of built-in .NET types returns null?

EDIT:
I suspect DateTime.ToString(invariantCulture) method with badly constructed culture settings.

Answer 1

I don't know of any types where it does. It's not impossible - it would certainly be easy to write your own type which behaved like that - but I doubt any of the framework types do.

Do you have any particular types in mind?

EDIT: DateTime.ToString(invariantCulture) should never return null - the culture settings should be irrelevant, if you've really got the invariant culture.

Answer 2

Correction, Object is not null if it returns null, NPE will thrown for null Object before toString() will be even tried to be invoked :)

Answer 3

You can also override the ToString() method and assign it a custom value. If it returns null still, then the object is null.

http://msdn.microsoft.com/en-us/library/ms173154%28v=vs.80%29.aspx