Month: February 2012

The Importance of SharePointWebPartCodeGenerator

Honestly, I have yet to actually enjoy SharePoint development specifically but, I still let myself learn. I want to briefly describe an issue I had when creating visual web parts in a sandbox solution. As the name of this entry implies, the SharePointWebPartCodeGenerator plays an important role in the web part creation. I will briefly describe what it is, where it is used, and why it is important. A basic knowledge of ASP.Net and developing in Visual Studio is necessary.

Huge Name, Small Functional Scope

The SharePointWebPartCodeGenerator is quite a self-descriptive name. It is a tool used to generate code for a web part. It is the “designer file” creator for the visual aspect of the SharePoint web part. Let me explain by describing what this is in average ASP.Net. In ASP.Net, pages and controls (ASPX and ASCX respectively) have a corresponding designer file. This is where the generated UI code is placed when a developer adds such things as “<asp:Textbox..” or “<asp:Literal..” etc etc. This is automated so it doesn’t usually affect the developer. The wonder that is the Visual Studio 2010 SharePoint Power Tools requires the use of the tool SharePointWebPartCodeGenerator. I’ll explain how and where to use this tool in the following sections.

Case in Point

I recently created a web part to display items from a list in a certain way and to wrap some specific functionality around those items. I went with a Visual Web Part. I find it a lot easier to develop a web user interface when it can actually be seen in HTML while I’m developing it. As usual, I found a better way to implement the web part only After I finished creating it. The change involved updating the controls used in the markup for the web part. After making the changes, I attempted to build the solution and got a nice error similar to:

‘..WebPart’ does not contain a definition for ‘userControlID’ and no extension method ‘userControlID’ accepting a first argument of type ‘..WebPart’ could be found (are you missing a using directive or an assembly reference?)

Looking at the project structure I noticed there was no designer file. Obviously, that is a problem! No designer file means that there is no code-behind support for the management of controls in my web part. I finally found that I needed to use a tool to create this designer file. I had to add ‘SharePointWebPartCodeGenerator’ to the ‘Custom Tool’ field of the markup file’s properties.

How-To

Let me describe this process. It is quite straightforward.

Make sure the markup file (e.g. .ascx) is selected in the Visual Studio project as shown below:

Select the ASCX In VS Solution Explorer

View the Properties of the markup file and make sure the ‘Custom Tool’ field contains ‘SharePointWebPartCodeGenerator’ as shown below:

Add SharePointWebPartCodeGenerator as CustomTool in ASCX's File Properties

This was all I needed to fix my issue. Making markup edits were no problem after I made that entry into the properties of the markup file. It now automatically runs the custom tool when I save my changes to the markup.

Run a System.Action Instantiation Asynchronously

Here is the second article in the Extension Me series. The Extension Me series focuses on various uses of Extension Methods in .NET and primarily uses C# as the language of choice. This article will briefly focus on the topic of Asynchronous Programming by extending System.Action delegates. Using the extension method, any code wrapped in an instantiation of System.Action delegates can be executed asynchronously. The assumptions made about the reader are: has experience with the basics of programming in C# and knows what extension methods are. Please be advised: the implications of asynchronous programming are not to be ignored for severe consequences can occur.

Not only is asynchronous programming fun and beneficial (if used correctly), it is becoming an essential skill as Windows 8 is introduced. Although the implementation of the following asynchronous pattern is incompatible with Metro-style WinRT apps, the theory of asynchronous programming will surely be applicable. More information on Asynchronous Programming can be found at Visual Studio Asynchronous Programming where How-To videos, whitepapers, samples, and walkthroughs are available.

Below is the implementation of the extension method:

public static class ActionExtensions
{
  public static void Async(this Action @this)
  {
    var thread = new Thread(@this.Invoke);
    thread.Start();
  }
}

The code snippet above shows how extension methods can introduce the beauty of System.Action and System.Threading.Thread objects working together. The Action and the Thread are very close. An essential function of System.Action is wrapping a block of executable code while an essential function of System.Threading.Thread is wrapping a block of execution. By embracing these two abilities, code can be executed asynchronously just by wrapping it in an Action delegate. Here is an example:

public void ReturnsQuick()
{
  new Action(() =>
  {
    //Long Running Code here runs on a separate thread…
  }).Async();
}

When the ReturnsQuick method is called, it creates a new instance of an Action passing a lambda containing “long-running code”. Using the extension method created previously, the code is executed on a separate thread. The code is now asynchronous and, as the name suggests, the ReturnsQuick method returns immediately after calling Async().

As mentioned above when introducing the topic of this article, there are plenty of caveats that must be addressed before adopting this approach (especially application-wide). Shared resource is one of the most important things to consider. If two threads try to access a single resource at the same time, one of them has to lose! Please take a look at the available pdf, “Threading in C#” by Joseph Albahari for a more detailed explanation of proper asynchronous approaches.

Serialization, Encryption, and Extension Methods Working In Harmony

Recently I wrote a blog entry called “Extension Me Serialize: With Encryption!” for Magenic focusing on encrypting serialized data. The url is: http://magenic.com/Blog/ExtensionMeSerializeWithEncryption.aspx and it has been referenced on Channel 9: http://channel9.msdn.com/Shows/This+Week+On+Channel+9/TWC9-Windows-8-C-Amp-NuGet-Mouse-Mischief-and-more.

Embracing the power of extension methods, I offered the ability to easily serialize objects while simultaneously offering security by default and defense in depth approaches. Also, as noted in the post, depending solely on encryption is not a responsible form of security for your IT system. The protection and maintenance of your encryption keys must be the first step. Encryption is meaningless unless the encryption keys are properly managed. If an attacker can easily access the encryption keys used for data encryption and can apply those to decrypt the data, the data is plaintext to them. I implore you, protect   your   keys !