What have I been up to?
Friday, September 21, 2007 10:20:01 PM (GMT Standard Time, UTC+00:00)
It's been rather quiet on my blog recently, if you're wondering why (and don't chat to me on/off-line) I thought I would share with you what we've been working on recently.
For the past month or so The Site Doctor has been developing a new web site (www.wineandhampergifts.co.uk) for Porter and Woodman Gifts Ltd - a local company that produces personalised corporate hampers and gifts. It's been quite a challenge as they have a rather unusual ordering system that allows multiple recipients/addresses multiple items. Looking at it now, it's not so complicated but the delivery charge calculations and initial specs took a while to fully grasp. It's been really enjoyable.
I'll probably cover aspects of the site over the forthcoming months but there are a few really nice features to the Wine and Hamper Gifts site (or at least I think so), some of which the end user will never know about such as the use of generics to calculate the address/recipient/gift variations) and those that they may -for instance the use of the JavaScript1 Zoom function on the product details page (courtesy of LuckyZoom), also the design created by our excellent designer Gareth Brown all adds up to what has to be one of the best sites I've developed to date.
1 Yes, I did just say I've integrated some JavaScript into the site ;)
I doubt most of my readers are interested on the in's and out's of the project itself but from an SEO perspective, I for one am expecting pretty decent results. We opted to use the URL Rewriting ISAPI from Helicon this time round over our usual IISMods URL Rewriting ISAPI as for some reason the IISMods site has been offline for a while (and checking now has been converted into a very weird site).
Another aspect that some people may be unaware of is that the majority of the Wine and Hamper Gifts site operates the same without JavaScript as it does with JavaScript, this is important not only for screen readers but also search engines. There is only one area of the Wine and Hamper Gifts site that I'm aware of that doesn't operate without JavaScript and that is the "Personalise this gift" link on the cart page that allows the user to either edit the existing message or add one that doesn't already exist, that's because it uses a LinkButton, but I may find a way around that later.
Other features that I really like are little things like the way the drop down lists on the left hand menu are created -they're not actually drop down lists but unordered lists that are then manipulated using JavaScript, I think the JavaScript could do with a little tweaking but the result is superb. The Wine and Hamper Gifts site also creates a PDF receipt for the user which is emailed to them, this is something I've been meaning to look into for some time but haven't had the chance, luckily while I was developing the site, Sean Ronan posted to the MsWebDev list about an ASP.Net PDF library iTextSharp (a port from a Java library) which, despite a few oddities from the POV of the Java port does exactly what I wanted. The library is pretty easy to use once you get your head around it and certainly produces some nice results.
There's still more work that's needed to finalise the content and various aspects of the Wine and Hamper Gifts website but if you have a chance, check out the new Porter and Woodman Gifts Ltd Wine and Hamper Gifts website and leave a comment here letting me know what you think :D
Oh, and they've given us a pretty high target to get before Christmas so if you're thinking about treating your customers to a personalised corporate hamper or gift give a little thought to using www.wineandhampergifts.co.uk
The Controls collection cannot be modified because the control contains code blocks
Friday, August 24, 2007 9:49:56 AM (GMT Standard Time, UTC+00:00)
Server Error in '/' Application.
The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Web.HttpException: The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).
Source Error:
| Line 132: metaKey.Name = "keywords";
Line 133: metaKey.Content = p.MetaKeywords;
Line 134: this.Page.Header.Controls.Add(metaKey);
Line 135: }
Line 136: if (!String.IsNullOrEmpty(p.MetaDescription)) |
Source File: a:\xyz\ContentHandler.aspx.cs Line: 134
Stack Trace:
| [HttpException (0x80004005): The Controls collection cannot be modified because the control contains code blocks (i.e. <% ... %>).]
System.Web.UI.ControlCollection.Add(Control child) +2105903
ContentHandler.Page_Load(Object sender, EventArgs e) in a:\xyz\ContentHandler.aspx.cs:134
System.Web.Util.CalliHelper.EventArgFunctionCaller(IntPtr fp, Object o, Object t, EventArgs e) +15
System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +34
System.Web.UI.Control.OnLoad(EventArgs e) +99
System.Web.UI.Control.LoadRecursive() +47
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +1061 |
Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832
Another day, another issue ;)
This had me going around in circles for a while until I realised what it was, if you're getting this error you can bet your bottom dollar that you have <%= %> somewhere in your page's header -furthermore I'd hazard a guess that you've got it in some JavaScript to reference an ASP.Net control on the page- and then you're trying to add a control to the header programmatically (or a custom control from someone like Telerik is trying to). Am I right1?
1 I'm not allowed to ask you to so I won't, but if I was right, then spend that bottom dollar clicking on one of the Google Ads :P
I can't tell you exactly why this occurs but my understanding of it is that ASP.Net can't re-create the header if it has Response.Write somewhere in the header (<%=) -most likely due to when the header is created it's not available (will look into it). No doubt you want to know the fix?
The Fix
The fix is simple, remove the inline code blocks and JavaScript and move it to your code behind i.e.:
Update: Thanks to Julian Voelcker for sending me this alternative "fix" for the problem, can't say I like it though ;) basically instead of using <%= ... %> you would write the databinding expression of: <%# ... %>
String.Format- Exception of type System.Web.HttpUnhandledException was thrown.
Wednesday, August 22, 2007 8:43:12 PM (GMT Standard Time, UTC+00:00)
Type
System.FormatException
Message
Exception of type 'System.Web.HttpUnhandledException' was thrown.
StackTrace
at System.Text.StringBuilder.FormatError()
at System.Text.StringBuilder.AppendFormat(IFormatProvider provider, String format, Object[] args)
at System.String.Format(IFormatProvider provider, String format, Object[] args)
Error Line
0
Just got that message (or at most "Exception of type 'System.Web.HttpUnhandledException' was thrown")? Puzzled? I was the first time I got it, I've been meaning to post about it for quite some time now so seeing as I got it again today I took the hint.
The error is horrifingly obvious when you know about it, in short, you've no doubt got some code that looks like this:
String.Format(
"<html><head><style type=\"text/css\">body{color: #fff;}</style><body>...");
Can you spot it now? Notice your style declaration is using the curly brackets? Basically String.Format is interpreting that as a placeholder i.e. {0} and is throwing a wobbly.
The solution is simple too, just replace all opening/closing brackets with two i.e:
String.Format(
"<html><head><style type=\"text/css\">body{{color: #fff;}}</style><body>...");
I hope that helps someone out there :)
P.S. Watch out for methods that use String.Format as they may catch you out in the same way -i.e. Subject of System.Net.Mail.MailMessage