Unlike the .NET platform, Silverlight only provides two text encodings out of the box: UTF-8 (UTF8Encoding class) and UTF-16 (UnicodeEncoding class).

Accordingly, if you find yourself in a situation where you need to encode or decode data with another encoding (e.g. iso-8859-1), you’ll have to write your own Encoding class (or delegate the work to a server-side service).

I found myself in this exact situation yesterday, and came up with a little tool which automates the process. The Encoding Generator is a WPF application which takes the name or code page of a well known encoding, and generates source code for a custom Encoding class which compiles under Silverlight.

Get Source Code

Get Compiled Executable

Current version: 1.0.0, 2010.03.31, requires .NET 3.5 SP1 or higher

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How Does It Work?

Specifying the Encoding

In order to specify the encoding you want to use, you can either enter the name or numeric code page of a well-known encoding. As soon as you enter a valid value, some information for the encoding is being displayed in the right hand border you can see on the screenshot.

As a sample for valid encoding names or code pages, here’s some values you can enter in order to tell the tool to generate an iso-8859-1 encoder (see screenshot):

• iso-8859-1 (name)
• latin1 (name)
• 28591 (code page)

A list of encodings can be found here.

Fallback Character

The tool gives you the option to specify a fallback character value, which is used as a default in case a character or byte value is being processed during encoding/decoding. In case you don’t specify the character, the encoding class will crash at runtime should it receive data that cannot be properly encoded or decoded.

Single-Byte Encoding Limitation

The generated class only works if a single byte can be translated into a single character and vice versa. Accordingly, if you try to generate code for an encoding that uses several bytes per (e.g. utf-8) character, the generator shows an error message.

Byte Range

You need to specify the byte range of the encoding. For example, ASCII supports only 128 characters, and therefore has a byte range of 128 bytes. Most other encodings support a byte range of 256 bytes, though. 256 is the maximum value that can be specified, as a single byte cannot deliver more values (the byte data type covers a numeric range from 0 – 255).

Testing

The generator also creates an NUnit test class that compares the results of the generated class against the original encoding. Accordingly, this test class is supposed to run in a regular .NET environment, not in Silverlight (if the original encoding that is used in the test was available in SL, you wouldn’t have to generate a custom encoding class in the first place…).

Internals

At runtime, the following is happening: Basically, the generator maintains mapping tables to do the encoding and decoding from characters to bytes and vice versa. Fore every request, it just looks up the translation tables for every supported character/byte value of the encoding.

The generator creates these translation tables on the fly in the form of a static array and dictionary.

Performance

The library doesn’t contain any performance tweaks and performs much slower than the built-in encodings that rely on all sorts of black magic. However, as long as you don’t have to encode or decode huge amounts of data, this shouldn’t be noticeable.

Here’s the results from my machine for 10000 iterations:

• Encoding the whole character table to a byte array (256 characters)
  • 17 milliseconds with the built-in encoding
  • 94 milliseconds with the generated encoding
• Decoding the bytes back into a string
  • 2 milliseconds with the built-in encoding
  • 46 milliseconds with the custom encoding

I like using CSS classes to format specific content of my blog posts, in order to keep my formatting centralized. I prefer HTML that looks like this over inline styles:

If you invoke the <span class="code">GetData</span> method, ...

Quickly inserting CSS directives is something you can’t easily do with Windows Live Writer. This started to annoy me while writing an article, so I came up with two simple plug-ins that do just that: Formatting selected text through CSS classes.

Read more…

I just posted an upgrade to my WPF NotifyIcon, which adds some minor improvements to the control. The most important one is probably the simplified data binding support for context menus (thanks to Nic Pillinger for the hint), but I also managed to add some polish in a few other areas.

Apart from the updated control itself, I completely revamped the sample project. It’s no longer just a showcase but contains various standalone samples which cover all aspects of the control. And last but not least, I published a complementary tutorial on the CodeProject. One could say I was quite busy

Further information and download on the project page:
http://www.hardcodet.net/projects/wpf-notifyicon

I’ve just uploaded installer and source code of NetDrives 1.0. This is my first tool that does not only address fellow developers, but a wider audience

In a few words, NetDrives is an open source utility that helps you manage your network shares and mapped network drives. Unlike Windows, it can reconnect to secured shares during startup and provides you quick access to your configured shares.

More information, screenshots, and downloads at the project page:

http://www.hardcodet.net/netdrives

Robby Ingebretsen published the source code of his incredibly useful (and beautiful!) Kaxaml on CodePlex. I often prefer Kaxaml over Visual Studio because it combines a bunch of really smart features with a very nice UI that just makes it a pleasure to work with. I’m definitely looking forward to have a peek at its internals

CodePlex project site: http://www.codeplex.com/Kaxaml
Official Kaxaml download site: http://www.kaxaml.com

A tutorial is now available on Code Project, so check the article for a detailed overview. And please leave your rating if you like the control
http://www.codeproject.com/KB/WPF/versatile_treeview.aspx

Update: The latest version is currently only available through the download link below. I’ll update the CodeProject article once the current filtering mechanism has been rewritten:

Download: wpf-treeview.zip (Current version: 1.0.7, updated 2008.04.06)

This is a little something I’ve been working on for a while: A replacement (or better: enhancement) of WPF’s built-in TreeView control.

I became aware of the default control’s limitations during my last project - I naturally started with hierarchical data templates, but was soon confronted with quite a few issues: I missed a simple API to control the tree, and styling of the tree’s nodes proved hard as well. Furthermore, WPF’s TreeView tends to fire all sorts of SelectedItemChanged events if it’s being refreshed or rebound, which caused side-effects with TwoWay data binding.

However, instead of posting a rant that probably nobody would ever read (let alone care about), I worked on an alternative. Here’s the tree’s main features at a glance:

• Simple declaration:

  <local:ProductTree x:Name="MyTree"
                     Items="{Binding Source={StaticResource Shop},
                            Path=Products}"
                     SelectedItem="{Binding ElementName=MyProductList,
                            Path=ActiveItem, Mode=TwoWay}"
                     NodeContextMenu="{StaticResource CategoryMenu}"
                     TreeNodeStyle="{StaticResource SimpleFolders}"
                     TreeStyle="{StaticResource SimpleTreeStyle}"
                     SelectedItemChanged="OnSelectedItemChanged"
  />

• Simple and type safe API:

  //bind flat list of business objects to tree
  List<Product> products = GetProducts();
  myTree.Items = products;
  
  //select a given item
  Product foo = GetBestSellingProduct();
  myTree.SelectedItem = foo; 
  
  //SelectedItem is of type Product - no casts required
  Product bar = myTree.SelectedItem;

• Lazy loading support - does not create tree nodes until the parent node is expanded. Also provides the option to automatically clear invisible tree nodes. This allows either virtualized trees in case getting data is expensive, or low memory trees that keep the number of tree nodes at a minimum.
• Simple sorting.
• Convenient context menu handling for tree nodes
• Optional root node which is not dependent on the tree’s bound items
• Simple styling on every level: Tree, TreeViewItem, or bound items (via DataTemplates).
• Tree layout can be cached, saved and reapplied.
• Access to tree nodes (TreeViewItem) through bound items.
• AutoCollapse feature / ExpandAll / CollapseAll methods

All this goodness comes at a price: The TreeViewBase class that provides this functionality, is abstract. This means you have to write a little code yourself. However, you’ll probably manage with 3 lines of code, as the base control just needs to know 3 things:

• How to generate an identifier for a given tree node
• How to access a bound item’s childs, if there are any
• How to access a bound item’s parent, if there is one

Here’s the complete implementation of the sample application’s tree control:

//a tree control that handles only ShopCategory objects
public class CategoryTree : TreeViewBase<ShopCategory>
{

  //the sample uses the category's name as the identifier
  public override string GetItemKey(ShopCategory item)
  {
    return item.CategoryName;
  }

  //returns subcategories that should be available through the tree
  public override ICollection<ShopCategory>
                             GetChildItems(ShopCategory parent)
  {
    return parent.SubCategories;
  }

  //get the parent category, or null if it's a root category
  public override ShopCategory GetParentItem(ShopCategory item)
  {
    return item.ParentCategory;
  }

I’m planning to write a CodeProject article for this one, but for now, it’s only available through my place without a tutorial. However: The library comes with a sample project that shows pretty much all features of the control. Project format is currently VS2008 only, but binaries which target .NET 3.0 are included. Enjoy!