The MSDN documentation for the is keyword says:
expression is not null
Why? If MethodThatReturnsNull() is type were called shouldn't that return false since null certainly isn't that type?
views:
108answers:
4
A:
The only thing you can say for certain about null is that you don't know what it is. Comparing something to null generally has a result of null ...
Q: Does 1 == "I don't know"? A: "I dont know"
Check out this blog post by Eric Lippert.
JP Alioto
2009-06-12 21:13:40
+3
A:
It does return false if expression is null. Perhaps you're misunderstanding the documentation?
mquander
2009-06-12 21:14:32
Correct. MSDN states "An is expression evaluates to true if the provided expression is non-null, and the provided object can be cast to the provided type without causing an exception to be thrown." So it is false if expression is null.
0xA3
2009-06-12 21:44:34
You're right, I misread the documentation.
jasonh
2009-06-12 21:44:54
I've voted to close it since it's not really relevant anymore, considering my mistake.
jasonh
2009-06-12 21:45:42
A:
This was a pretty popular answer I gave to a similar question.
http://stackoverflow.com/questions/930147/c-get-type-of-null-object/930155#930155
That's like asking what kind of cake would have been in an empty box with no label.
Josh Einstein
2009-06-12 21:15:43
According to the C# compiler and .NET framework, it's not a <i>type</i> cake. :)
jasonh
2009-06-13 01:33:26