Using a script to set the Copy Local flag to false

As with my previous post I recently came across a repeatable task that we will probably want to repeat in the future so with my aim from The Pragmatic Programmer I decided to automate it.

The problem was that an architecual requirement of this project was to rely on DependencyInjection for all library references. To help enforce this every project outside of the DI one would require the Copy Local flag on all references set to false.

I started doing this manually but figured out it'd take a long time to go through all 40+ projects and this would happen in the future. So automation time it was.

A quick web search did not show that anyone had solved this problem before so I figured out I would have to learn some Powershell and make it myself.

As csproj files are simply XML I did some research to find out how easy it was to manipulate XML in Powershell. It turned out this is one of Powershell's strengths. However the first implementation had issues with namesapces so I had to use the Select-Xml command introduced in Powershell v2.

Building the XPath queries was fairly simple. The one hiccup to remember is that csproj xml has a default namespace of "http://schemas.microsoft.com/developer/msbuild/2003" so you need to remember to use that and the msb namespace prefix when making your XPath queries. To specify the namespace in Select-Xml you use the -namespace option.

Select-Xml -namespace @{msb = $projectNamespace} -xpath $privateXPath

The next step was saving out the changes. This proved to be an initial roadblock as all the files were set to readonly. As we are using TFS you have to explicitly checkout the files before you can edit them. This resulted in me looking into how to use the TFS command line executable "tf.exe". This proved to be fairly nice as I could simply pipe the collection of csproj files I wanted checked out to a chunk of script that would iterate through the collection and execute the checkout command on each file with the provided TFS credentials.

I explicitly did not attempt to check in the changes as I want the user to review the changes and make sure the solutions are still working. This is something you'd run once a month to make sure the requirement is still being followed.

The final hiccup was that the .NET XML classes Powershell uses has an issue with putting in a default empty namespace whenever you create a new element. This caused the project to fail to load in VisualStudio as the namespace was incorrect. The fix for this was pretty quick and easy. Take the file and replace any occurance of xmlns="" with an empty string. This is accomplished in Powershell with line

(Get-Content $projFilenameFull) | Foreach-Object {$_ -replace ' xmlns=""', ""} | Set-Content $projFilenameFull

So my first non-trivial powershell script was a fun and fiddly dive into scripting all my troubles away. So far so good. ;)

SetCopyLocalInAllCsProjFiles.ps1

Deleting all bin and obj folders from a solution

Quick little post.

Since reading The Pragmatic Programmer by Andrew Hunt and David Thomas I've been looking for ways to automate tasks whenever I find myself doing something I know I'm going to repeat later or I'm repeating right there and then.

The other day I was working on a VisualStudio Solution someone else had started and when trying to build it found they had checked in some of the bin and obj folders.

So I open up the root folder of the solution and prepare to trawl through about a dozen projects to delete all the bin and obj files. Obviously noticing that I'm about to do the same steps repeatedly and this will happen in the future I went and did a quick search to see if anyone else had already solved this.

Awesomely someone had.

So a huge thanks to Glenn at Development on a shoestring for providing exactly what I needed. I'm putting this here just in case his site should disappear and take the knowledge with it.

I threw the following into a powershell script that sits in source control ready for use in the future

# Iterate through all subdirectories and delete all bin and obj folders
# http://blog.slaven.net.au/2006/11/22/use-powershell-to-delete-all-bin-obj-folders/
# Had to use it for getting rid of a bunch of bin and obj folders in a PoC but thought it smart to put in here for other to use
Get-ChildItem .\ -include bin,obj -Recurse | foreach ($_) { remove-item $_.fullname -Force -Recurse }

RemoveAllBinAndObjFolders.ps1

Event Handlers only firing once in Microsoft Office AddIns

I've just been working on a project where we were to create some AddIns for several versions of Microsoft Office. Now I knew there was a lot of bad blood around Office AddIns but thought they were being overblown as I finished off the 2010 AddIn without so much as a hiccup. The 2007 and 2003 AddIns however showed why Office has the reputation it has.

The problem I ran into was that I had to have several event handlers to catch two events. The opening of a new inspector and a simple button click. So I did what you'd expect to do and registered them in the startup methods.

Initial testing went fine as I started up Outlook and triggered one event, made some changes, restarted it and then tested the other event. It took a while until I tried to test both events following one another at which point I found only one would trigger and then both would even handler hooks would be forgotten and wouldn't rehook in until a restart of the application.

public partial class ThisAddIn
{
    private void ThisAddIn_Startup(object sender, System.EventArgs e)
    {
        Outlook.Explorer explorer = this.Application.ActiveExplorer();
        Outlook.Application app = (Outlook.Application)explorer.Application;

        app.NewInspector += new InspectorsEvents_NewInspectorEventHandler(Inspectors_NewInspector);
    }
}

After much searching I began to come across implications that the garbage collector was removing the references after the first event. I was at a loss at what to do until I came across another discussion where someone was having a similar problem and the response was to save the object in a class level variable to avoid the garbage collector from removing it.

A quick edit and some testing showed this to work reliably. So, if Office is only triggering an event once make sure there object references are stored somewhere the garbage collector won't go. And make sure to assign the object before you register the handler or the garbage collector will still find it.


public partial class ThisAddIn
{
    public Inspectors _appInspectors;

    private void ThisAddIn_Startup(object sender, System.EventArgs e)
    {
        Outlook.Explorer explorer = this.Application.ActiveExplorer();
        Outlook.Application app = (Outlook.Application)explorer.Application;

        _appInspectors = app.Inspectors;
        _appInspectors.NewInspector += new InspectorsEvents_NewInspectorEventHandler(Inspectors_NewInspector);
    }
}

Playing with Regex on OSX

RegExhibit

If you've ever been stuck with the problem of trying to build anything but a simple regular expression you know how painful it can be getting it to match just what you want.

When developing for .NET on Windows I was introduced to a brilliant free tool called Rad Software Regex Designer that gave you the ability to provide an example of the text you wanted to match and an area to slowly build up your regular expression while getting instant feedback on what it was doing. It even has dialogs to add specific regular expression commands in case your proficiency with regular expressions isn't high or you just forgot how to create a non matching group. After moving to OSX for work I went looking for a similar tool for the Mac. And after a while I found it.

RegExhibit is a GUI tool of OSX that uses the Perl regular expression library to help you build regular expressions. This should be fine for any other languages that use a PCRE library but make sure you check before deploying. The core part of the program are two text areas. you place an example of the text you want to match into the lower area and build up your regular expression in the top are. There are even tabs for doing matches and splits but you'll likely find yourself in the match tab for most of time. However it doesn't offer the same built in dialogs like the Rad Software Regex Designer so make sure you've got a regular expression reference handy.

This is a great tool that has saved my sanity several times already and I do recommend to anyone that has to play with regular expressions and is developing on the Mac.

Adding Attachments with ActionMailer

Well recently I had the fun task of using Ruby on Rails' ActionMailer to create some automated emails to send out to users. At some point it was decided to attach the original email we received from the user to the notification email we were sending out to the user.

Now you would think that using the attachments method provided by ActionMailer would make it a easy as just giving it the file you wanted to add. Turns out it's like that for Ruby on Rails 3, not for 2.

The most infuriating thing was that if you use the attachments method then the method you called attachments from will not render the default view template it would normally. This means you have to explicitly call the render method.

Instead of putting it out all nicely I'll just link to a blog post from ELCtech.com that explains it well. http://www.elctech.com/ -- [ActionMailer] Multipart emails with attachments