?? and Guid

[shapper]

Hello,

I am inserting an item on a XML file and I have something like this:

paper.ID ?? Guid.NewGuid()

Basically my idea was that if paper.ID is null then create a new Guid.

It says it is not possible to use ?? with Guid. Is there another
option to do this?

Thanks,
Miguel

[=?iso-8859-1?B?S2VyZW0gR/xtcvxrY/w=?=]

Hi Miguel,

can you show code please,...
Regards

Kerem

--
-----------------------
Beste Grüsse / Best regards / Votre bien devoue
Kerem Gümrükcü
Latest Project: http://www.codeplex.com/restarts
Latest Open-Source Projects: http://entwicklung.junetz.de
-----------------------
"This reply is provided as is, without warranty express or implied."
"shapper" <md*****@gmail.comschrieb im Newsbeitrag
news:cb**********************************@d45g2000 hsc.googlegroups.com...

Hello,

I am inserting an item on a XML file and I have something like this:

paper.ID ?? Guid.NewGuid()

Basically my idea was that if paper.ID is null then create a new Guid.

It says it is not possible to use ?? with Guid. Is there another
option to do this?

Thanks,
Miguel

[Family Tree Mike]

A Guid cannot be null, unless you declare it Guid?.

"shapper" <md*****@gmail.comwrote in message
news:cb**********************************@d45g2000 hsc.googlegroups.com...

Hello,

I am inserting an item on a XML file and I have something like this:

paper.ID ?? Guid.NewGuid()

Basically my idea was that if paper.ID is null then create a new Guid.

It says it is not possible to use ?? with Guid. Is there another
option to do this?

Thanks,
Miguel

[shapper]

On Sep 8, 3:42*am, Kerem Gümrükcü <[e-mail]:

Hi Miguel,

can you show code please,...

Regards

Kerem

--
-----------------------
Beste Grüsse / Best regards / Votre bien devoue
Kerem Gümrükcü
Latest Project:http://www.codeplex.com/restarts
Latest Open-Source Projects:http://entwicklung.junetz.de
-----------------------
"This reply is provided as is, without warranty express or implied."
"shapper" <[e-mail] im Newsbeitragnews:cb******************************** **@d45g2000hsc.googlegroups.com...

Hello,

I am inserting an item on a XML file and I have something like this:

paper.ID ?? Guid.NewGuid()

Basically my idea was that if paper.ID is null then create a new Guid.

It says it is not possible to use ?? with Guid. Is there another
option to do this?

Thanks,
Miguel

album.Add(new XElement("img",
new XAttribute("id", paper.Slide.SlideID ??
Guid.NewGuid())
));

paper.Slide is an object. So if it's SlideID, which is Guid, had no
value assigned then a new guid is used.

This seemed logic to me until I got the error :-)

[shapper]

On Sep 8, 4:07*am, "Family Tree Mike"
<[e-mail]:

A Guid cannot be null, unless you declare it Guid?.

"shapper" <[e-mail] in message

news:cb**********************************@d45g2000 hsc.googlegroups.com...

Hello,

I am inserting an item on a XML file and I have something like this:

paper.ID ?? Guid.NewGuid()

Basically my idea was that if paper.ID is null then create a new Guid.

It says it is not possible to use ?? with Guid. Is there another
option to do this?

Thanks,
Miguel

Well, I can do this:

Guid id = new Guid();

And yet the Guid value is not defined.

[=?Utf-8?B?TW9ydGVuIFdlbm5ldmlrIFtDIyBNVlBd?=]

"shapper" wrote:

On Sep 8, 3:42 am, Kerem Gümrükcü <[e-mail]:

Hi Miguel,

can you show code please,...

Regards

Kerem

--
-----------------------
Beste Grüsse / Best regards / Votre bien devoue
Kerem Gümrükcü
Latest Project:http://www.codeplex.com/restarts
Latest Open-Source Projects:http://entwicklung.junetz.de
-----------------------
"This reply is provided as is, without warranty express or implied."
"shapper" <[e-mail] im Newsbeitragnews:cb******************************** **@d45g2000hsc.googlegroups.com...

Hello,

I am inserting an item on a XML file and I have something like this:

paper.ID ?? Guid.NewGuid()

Basically my idea was that if paper.ID is null then create a new Guid.

It says it is not possible to use ?? with Guid. Is there another
option to do this?

Thanks,
Miguel

album.Add(new XElement("img",
new XAttribute("id", paper.Slide.SlideID ??
Guid.NewGuid())
));

paper.Slide is an object. So if it's SlideID, which is Guid, had no
value assigned then a new guid is used.

This seemed logic to me until I got the error :-)

Since SlideID is a Guid it cannot be null. Therefore SlideID ?? makes no
sense. Now, if you make SlideID a Guid? (nullable Guid) your code should
work.

--
Happy Coding!
Morten Wennevik [C# MVP]

[Alex Meleta]

Hi shapper,

Yes, but cant Guid id = null. Basicaly, ?? aplied for reference and nullable
types.
http://msdn.microsoft.com/en-us/libr...24(VS.80).aspx

Regards, Alex
blog: devkids.blogspot.com

Well, I can do this:

Guid id = new Guid();

And yet the Guid value is not defined.

[Jon Skeet [C# MVP]]

shapper <md*****@gmail.comwrote:

Well, I can do this:

Guid id = new Guid();

And yet the Guid value is not defined.

Yes it is. That's a well-defined Guid of all zeroes. It's sort of like
the empty string of Guids.

--
Jon Skeet - <sk***@pobox.com>
Web site: http://www.pobox.com/~skeet
Blog: http://www.msmvps.com/jon.skeet
C# in Depth: http://csharpindepth.com

[shapper]

On Sep 8, 6:08*am, Morten Wennevik [C# MVP]
<[e-mail]:

"shapper" wrote:

On Sep 8, 3:42 am, Kerem Gümrükcü <[e-mail]:

Hi Miguel,

can you show code please,...

Regards

Kerem

--
-----------------------
Beste Grüsse / Best regards / Votre bien devoue
Kerem Gümrükcü
Latest Project:http://www.codeplex.com/restarts
Latest Open-Source Projects:http://entwicklung.junetz.de
-----------------------
"This reply is provided as is, without warranty express or implied."
"shapper" <[e-mail] im Newsbeitragnews:cb******************************** **@d45g2000hsc.googlegroups.com...

Hello,

I am inserting an item on a XML file and I have something like this:

paper.ID ?? Guid.NewGuid()

Basically my idea was that if paper.ID is null then create a new Guid.

It says it is not possible to use ?? with Guid. Is there another
option to do this?

Thanks,
Miguel

* * * album.Add(new XElement("img",
* * * * * * * * * new XAttribute("id", paper.Slide.SlideID ??
Guid.NewGuid())
* * * * * * * * ));

paper.Slide is an object. So if it's SlideID, which is Guid, had no
value assigned then a new guid is used.

This seemed logic to me until I got the error :-)

Since SlideID is a Guid it cannot be null. *Therefore SlideID ?? makes no
sense. *Now, if you make SlideID a Guid? (nullable Guid) your code should
work.

--
Happy Coding!
Morten Wennevik [C# MVP]

I see. I think I will let it this way because it is generated by Linq
To SQL dbml and I prefer to touch the least possible in the generated
code.

[shapper]

On Sep 8, 6:22*am, Jon Skeet [C# MVP] <[e-mail]:

shapper <[e-mail]:

Well, I can do this:

Guid id = new Guid();

And yet the Guid value is not defined.

Yes it is. That's a well-defined Guid of all zeroes. It's sort of like
the empty string of Guids.

--
Jon Skeet - <[e-mail]>
Web site:http://www.pobox.com/~skeet*
Blog:http://www.msmvps.com/jon.skeet
C# in Depth:http://csharpindepth.com

You are completely right!

Thanks,
Miguel