Enumerating projects in a Visual Studio solution

People writing add-ins for Visual studio probably have come across the nightmare of the Visual studio object model to go through the projects within a solution. I had to get the list of projects in a solution, and for each solution its output path in the current configuration. Although I need the code in C# later on, the best way to check out how to program against the Visual Studio object model is within the Macro IDE of Visual Studio (Tools->Macros->Macros IDE).

Although the question seems quite straightforward, the trouble begins when you have Solution Folders containing projects. The Solution object has a property called Projects, but Solution Folders are also seen as Projects. A project has project items. A project item can be a folder, a file, or... a project. You have to see it to believe the mess.

After a lot of trial and error I got to a solution where I check if a project item has its ConfigurationManager property set, if this is the case, it must be a project. Not sure if this is the best approach, but it works for me. For example for the following project structure using Solution Folders:

I get the following output:

And the code to accomplish this (paste in  Macros IDE):

Sub SolutionProjects()
        Dim project As EnvDTE.Project
        Write("--------- DUMP OF ALL PROJECTS IN CURRENT SOLUTION -------------")
        Try
            If Not DTE.Solution.IsOpen Then
                Write("There is no solution open.")
            Else
                For Each project In DTE.Solution.Projects
                    NavProj(project)
                Next
            End If
        Catch ex As System.Exception
            Write(ex.ToString)
        End Try
    End Sub
    Sub NavProj(ByVal proj As Project)
        Dim outputPathProperty As EnvDTE.Property
        Dim outputPath As String
        If Not (proj.ConfigurationManager Is Nothing) Then
            ' It's a project!
            outputPathProperty = _
proj.ConfigurationManager.ActiveConfiguration.Properties.Item("OutputPath")
If outputPathProperty Is Nothing Then
                outputPath = "<no output path set>"
            Else
                outputPath = outputPathProperty.Value
End If
            Write("### Project: " + proj.Name + ", OutputPath: " + outputPath)
Else
            NavProjItems(proj.ProjectItems)
End If
    End Sub
    Sub NavProjItems(ByVal projItems As ProjectItems)
Dim projectItem As EnvDTE.ProjectItem
    <span style="color: rgb(0,0,255)">If</span> <span style="color: rgb(0,0,255)">Not</span> (projItems <span style="color: rgb(0,0,255)">Is</span> <span style="color: rgb(0,0,255)">Nothing</span>) <span style="color: rgb(0,0,255)">Then

            For Each projectItem In projItems
If Not (projectItem.SubProject Is Nothing) Then
                    ' Recurse, can be an Enterprise project in
                    ' Visual Studio .NET 2002/2003 or a solution folder in VS 2005
                    NavProj(projectItem.SubProject)
End If
            Next
        End If
    End Sub
    Sub Write(ByVal s As String)
Dim out As OutputWindowPane = GetOutputWindowPane("MACRO OUTPUT", True)
out.OutputString(s)
out.OutputString(vbCrLf)
End Sub

    Function GetOutputWindowPane(ByVal Name As String, Optional ByVal show As Boolean = True) As OutputWindowPane
Dim win As Window = DTE.Windows.Item(EnvDTE.Constants.vsWindowKindOutput)
If show Then win.Visible = True
        Dim ow As OutputWindow = win.Object
Dim owpane As OutputWindowPane
Try
            owpane = ow.OutputWindowPanes.Item(Name)
Catch e As System.Exception
owpane = ow.OutputWindowPanes.Add(Name)
End Try
        owpane.Activate()
Return owpane
End Function