In This Issue...

Build Your Own ASP.NET Website Using C# & VB.NET

Learn to build dynamic ASP.NET Websites using freely available software with no programming experience. Learn ASP.NET by building:

• a password-protected Intranet
• an ecommerce store
• a shopping cart system with credit card processing
• a newsletter system
• and much more!

All the content is presented in a fun, practical and easy-to-understand style. All you need to get started is a recent version of Windows and knowledge of HTML! (More information...)

Introduction

Thanks to some hasty hardware handling by yours truly, I had smoke come out of my computer last weekend! Can you guess which part did the smoking?

Computer parts are pretty well designed these days, so as you might expect the part that I was able to plug in wrong to cause a short circuit was the antiquated floppy drive.

As incendiary incidents go, I was happy to get away with a new floppy drive and a little electrical tape. Bullet dodged, I say, as at the other end of the short circuit was one of my hard drives.

SitePoint's Around the World photo competition is winding down with less than a week to get in for your chance to nab an iPod. With all the fantastic entries so far, we're still lacking some major landmarks like the Eiffel Tower, the Grand Canyon, the Sydney Opera House, and the Olympic village. Live close to a famous landmark? You might be surprised just how easy it is to win in this contest... <hint, hint...>

PNG Panic

All this week I've been brewing up a big rant for you about Internet Explorer's PNG support sliding further downhill in Windows XP Service Pack 2. Turns out things weren't nearly as bad as I feared. Now I'm just confused...

Way back in the Tech Times #44, I explained a somewhat clunky workaround that let you display a partially transparent PNG image in both Internet Explorer and other browsers. I ended that particular tip with these naively hopeful words:

Let's just hope that Microsoft wise up and support PNG transparency with the standard <img> tag in Internet Explorer 7!

Now, more than two years later, not much has changed.

Over the weekend, I was working for the first time since installing SP2 on a site I designed recently that uses PNG transparency in the main logo at the top of every page. When I previewed my work in Internet Explorer, I was shocked to see it display a warning about active content as it refused to display the logo!

The cause? Well, though you may not realize it, you need to use an ActiveX control to display PNG transparency in Internet Explorer.

filter:progid:DXImageTransform.Microsoft.
    AlphaImageLoader(src='logo.png');

In this IE-only CSS property, which displays a PNG file with transparency in that browser, DXImageTransform.Microsoft.AlphaImageLoader is actually an ActiveX control. And at first glance, it looked to me like Internet Explorer had decided to block its use by default. Disaster!

Today I got around to visiting the live version of the site in Internet Explorer, and I was both relieved and suspicious when the security warning didn't pop up. Had it all been some bizarre nightmare?

It turns out that, by default, Internet Explorer only blocks the PNG transparency control when loading a page from your computer (i.e. with a file:// URL). Near as I can figure, someone decided that allowing ActiveX controls to access local files was a security risk. Personally, I'd have liked to have seen an exception made for this particular control.

For semi-official information and discussion about PNG support in Internet Explorer, see the Channel9 Wiki.

HTML Utopia - Learn CSS the Easy Way!

Crossing the Great Divide

At the risk of scaring off some of the less advanced readers, I'm continuing to follow Harry Fuecks' efforts to develop ScriptServer, a framework that allows JavaScript code in the browser to execute PHP code on the server.

SitePoint's PHP blog has had suspiciously little PHP and a whole lot of JavaScript in it lately. With the latest installment in his Crouching JavaScript, Hidden PHP saga, Harry revealed the method to this madness.

Throughout Web history, there has been a Great Divide between server-side code and client-side code:

• On the server side, code such as PHP scripts are used the process form submissions and generate Web pages dynamically from databases and other sources.
  
• On the client side, JavaScript code (and occasionally Flash movies and Java applets) display friendly, usable interfaces to the user.

Until recently, the only pass over this Great Divide that would allow client-side interface code to use server-side processing code has been the browser's page request mechanism. That is to say, the client-side code can do all the lovely interface stuff it likes, but the moment it needs to get information from the server, a new Web page must be loaded to obtain that information.

Last issue, I explored some recent developments in browser technology that have begun to suggest alternative routes across the Great Divide. It is fast becoming practical for JavaScript code to interact with the server between page requests. Similar trends can be seen in the world of Flash (e.g. Flash Remoting).

Harry's ScriptServer project aims to pave a nice, smooth four-lane highway right over the Great Divide. Rather than forever futzing with differing implementations of XMLHttpRequest to get the slightest practical result, you should be able to simply add the ScriptServer library to your page and then start coding as if JavaScript and PHP were one.

ScriptServer has got a ways to go before it's something you'd use in a public Website, but when the stars align and the wind blows the right way the alpha version is already quite a thing to see in action.

If being up to your elbows in JavaScript and PHP at the same time is your idea of a good time (I can't be the only one, surely...), then check out Harry's work and think about pitching in.

If not, just sleep sound in the knowledge that the Great Divide may be shrinking by the day.

Read the blog entry:

PHP Blog: Dynamically Typed by Harry Fuecks Crouching JavaScript, Hidden PHP [3] (22 comments)

That's all for this issue -- thanks for reading! I'll see you in two weeks.

Kevin Yank
techtimes@sitepoint.com
Editor, The SitePoint Tech Times

Help Your Friends Out

• problem with input type=file
  in CSS
  
  
• Add a CSS class using Javascript?
  in JavaScript
  
  
• Rhyming Words
  in PHP
  
  
• Cart Data in Sessions or Database?
  in PHP
  
  
• JS and CSS Compression with PHP
  in PHP
  
  
• another OOP question
  in Advanced PHP Programming
  
  
• How many CMS's do there need to be?
  in Scripts and Online Services
  
  
• Firefox Preview Release
  in General Chat
  
  
• What Every Web Designer Needs to Know
  in General Development Issues
  
  
• CVS v SVN
  in Advanced PHP Programming
  
  
• ms word curly quotes
  in Perl, Python and Other Languages
  
  
• Microsoft touts Sender ID
  in General Chat
  
  
• Class Methods as Request Actions in MVC
  in Advanced PHP Programming
  
  
• Version Control Systems (Windows)
  in General Development Issues
  
  

.NET Blog:
Daily Catch

• Setting Page Titles 2005 Style
  1 comments
  
  
• SQL Server 2005 Express via ODBC?
  
  
• Mathematical Expression Compiler
  
  

PHP Blog:
Dynamically Typed

• Horde: first signs of a COM for PHP
  1 comments
  
  
• Get your blog and PHP on the map
  7 comments
  
  
• The Standard PHP Library: Worse gets better
  4 comments
  
  
• Walking the walk vs. talking the talk
  3 comments
  
  

Open Source Blog:
Open Sourcery

• Open Source Coming of Age
  
  
• Checking for Rootkits
  1 comments
  
  
• Subversion Tips for CVS Users
  
  
• International Review of Open Source Policies
  1 comments
  
  

ColdFusion Blog:
InFused

• Blackstone in beta Officially
  3 comments