Customer Support - Can't delete anything

Imar · November 22nd, 2007, 05:17 PM

Do you get this error with the original source downloaded from this web site and just the fix I recommended?

In the code you posted I can't find a reason for the error you're getting.....

Imar
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Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of ASP.NET 2.0 Instant Results and Beginning Dreamweaver MX / MX 2004
Want to be my colleague? Then check out this post.

john77 · November 23rd, 2007, 06:00 AM

Hi Imar

Thanks for your reply.

I made your fixes to source I obtained from book CD not site download.

So I'll try downloading source from site instead.

Rgds, John

Imar · November 23rd, 2007, 07:29 AM

That shouldn't make a difference. The code from the CD is pretty much the same as the code on-line, except for the stuff in the errata section.

I was referring to any customizations you made. Like I said, the code you posted can't generate the error you posted.

Maybe you check your code, set a break point in it and see where it crashes exactly? Once you post the relevant code, it's easier for me to suggest a fix.

Cheers,

Imar

---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of ASP.NET 2.0 Instant Results and Beginning Dreamweaver MX / MX 2004

john77 · November 23rd, 2007, 08:39 AM

Hi Imar

I reinstalled source from CD, made no changes other than your 2 fixes in Products.aspx and Products.aspx.vb but got same result as I originally stated, that is:

I get following error:

  "Unable to cast object of type 'System.Web.UI.LiteralControl' to
   type 'System.Web.UI.WebControls.Button'."

Error occurs in this line(36) of gvProduct_RowCreated Event in Products.aspx.vb:

  Dim myButton As Button = CType(e.Row.Cells(3).Controls(0), Button)

Any other ideas?

Thanks for help so far.

Rgds, John

Imar · November 23rd, 2007, 04:57 PM

Hi John,

I think I found the issue.

Initially, the code in the code behind (in gvProduct_RowCreated) to be exact) was responsible for finding the button and adding the onclick handler. The code assumed that the Button was the first control in the cell (which is correct if you use a BoundField.

By converting to a <ItemTemplate>, this is no longer the case, and thus the code crashes when it tries to use the myButton variable.

The fix is simple though; just comment out all code in the gvProduct_RowCreated handler; or better yet: remove the entire handler.

My current working copy of the Customer Support Site had this code commented out as well, from last time I fixed this. Apparently, I forgot to post this information (as I warned in my post, my brain was melting at that time) and the OP never posted a follow up on that.

Hope this helps,

Imar
---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of ASP.NET 2.0 Instant Results and Beginning Dreamweaver MX / MX 2004
Want to be my colleague? Then check out this post.

john77 · November 26th, 2007, 06:11 AM

Hi Imar

Thanks for explanation and fix - now works okay.

Weird thing is I commented out that event before and it lead to a different error message, though this was with the code i'd already made several other changes to.

I'll now take my time amending the reloaded project.

All the best, John

Imar · November 26th, 2007, 04:19 PM

You're welcome. Good luck....

Imar

---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of ASP.NET 2.0 Instant Results and Beginning Dreamweaver MX / MX 2004

hrdndogs · June 23rd, 2009, 02:58 PM

First I would like to say "thank you" to the authors of this book. It has been very educational and usefull.

Second I would like to point out a missing piece in the errata for the book, this code

Code:

 CommandArgument='<%# Eval("Id") %>'

was missing in the errata. Once I figured out what was supposed to be there all is good.

Thanks again

Imar · June 24th, 2009, 03:39 PM

Hi hrdndogs,

You're welcome; good to hear you like the book.

Took me a while to figure out what exactly you were saying. I knew the CommandArgument was in the errata so I didn't understand the problem. Now I see that the "<%# Eval("Id") %>" is missing from the CommandArgument..

I'll have it fixed as soon as possible. Thanks for reporting it.

Cheers,

Imar

Imar · June 24th, 2009, 03:41 PM

Heuh? I just noticed if you copy and paste the errata, the code *is* there? Try this:

Go here: http://www.wrox.com/WileyCDA/WroxTit...Cd-ERRATA.html

Select the text with the CommandArgument in bold, copy it and paste it in Notepad. Do you get Eval("ID") ??

Weird...

Imar