Cannot redirect to ManagePhotoAlbum

GeeTee991100 · December 11th, 2010, 12:13 PM

Hi,

I've tried the try it out that starts on page 444 and the continue one that starts on`page 452 and I cannot get the NewPhotoAlbum page to redirect to the ManagePhotoAlbum page. I've gone through it step by step twice and still have no joy. I get the following error.

http://i156.photobucket.com/albums/t13/GRiT_02/add.jpg

The Site structure is as follows

http://i156.photobucket.com/albums/t..._02/folder.jpg

Both files seems to be there.

Can you help?

Thanks

GeeTee991100 · December 11th, 2010, 03:13 PM

Hi,

I'm still having this problem.

I've even copied the source code from the Chapter 13 folder. Just the two files and I still get the issue. If I load in the whole of chapter 13 it works so I think there must be something I've missed but I've now followed the steps 3 times. Can anyone help?

Thanks

Imar · December 11th, 2010, 04:49 PM

Hi there,

My guess is that this is not related to the redirect or structure of your site, but to your LINQ to SQL model. I think myPhotoAlbum is null, and causes the error..

Did you correctly create the database, the relationship between the tables and the L2S model (and in that order)?

Try debugging the Inserted method (debugging is explained in Chappter 17) and then look at e.Exception (e is an argument of the Inserted handler). Does it contain an error message?

Cheers,

Imar

GeeTee991100 · December 11th, 2010, 05:55 PM

Thanks for the response.

By using some old school techniques I worked out the issue was with the database. I get the message "Cannot insert explicit value for identity column in table 'PhotoAlbum' when IDENTITY_INSERT is set to OFF."

Do you know what that means?

Thanks

EDIT: Forgot to mention that I've re-imported the chapter 13 database and still get this issue.

Imar · December 11th, 2010, 07:29 PM

That sounds like you make the Id column an identity in the database *after* you created the LINQ to SQL model in Visual Studio. When that happens, L2S doesn't know that Id is an identity generated by the database. This in turn means it will try to supply a value (which is zero in this case - the default for a non nullable Integer) when you try to save the changes. The database then raises an exception because it receives an explicit value for a column that it's supposed to automatically generate.

If this is indeed the problem, the easiest solution to this is to recreate the L2S model; just remove the tables from the model, and drag them onto the design surface again from the Database or Server Explorer. Note, this is about the L2S model / diagram; not about the database diagram.

Hope this helps,

Imar

GeeTee991100 · December 11th, 2010, 07:48 PM

I deleted all the chapter 13 files re-created the tables and the L2s link and it worked, Thanks for your help.

Imar · December 12th, 2010, 06:44 AM

Good to hear it's working. I think only recreating the L2S model would have been enough, but hey, if it works, it works.... ;-)

Cheers,

Imar