Comparing to DBNull

[Michael Culley]

Which is better:

SomeValue is DBNull
or
SomeValue == DBNull.Value

Thanks,
Michael Culley

[googou]

I think this is better:
Convert.IsDBNull(SomeValue);

and the 'is' keyword can not be used in this case
"Michael Culley" wrote:

Which is better:

SomeValue is DBNull
or
SomeValue == DBNull.Value

Thanks,
Michael Culley

[Jon Skeet [C# MVP]]

googou <go****@discussions.microsoft.com> wrote:

I think this is better:
Convert.IsDBNull(SomeValue);

and the 'is' keyword can not be used in this case

Yes it can. The only value of DBNull is DBNull.Value - any reference
which "is" a DBNull is DBNull.Value, so

if (x is DBNull) is exactly equivalent to if (x==DBNull.Value). The
only difference using Convert.IsDBNull is if x is an instance of a type
which implements IConvertible with a GetTypeCode method returning
TypeCode.DBNull.

--
Jon Skeet - <sk***@pobox.com>
http://www.pobox.com/~skeet
If replying to the group, please do not mail me too

[Marcin Grzêbski]

Hi!

From my PoV:
"SomeValue == DBNull.Value"
should be faster than
"SomeValue is DBNull"

In the first case the only reference is compared.
The second case is Type compatibility comparison that
i believe need more time.

Of course these cases work in 100%!

Cheers!

Marcin

Which is better:

SomeValue is DBNull
or
SomeValue == DBNull.Value

Thanks,
Michael Culley

[Ignacio Machin \( .NET/ C# MVP \)]

Hi,

"Marcin Grzêbski" <mg*******@taxussi.no.com.spam.pl> wrote in message
news:cj**********@nemesis.news.tpi.pl...

Hi!

From my PoV:
"SomeValue == DBNull.Value"
should be faster than
"SomeValue is DBNull"

I agree with you, it's faster and IMO more legible.
cheers,

--
Ignacio Machin,
ignacio.machin AT dot.state.fl.us
Florida Department Of Transportation