Powershell function that recursively walks all project items within a project and lets you execute an action on each one

Examples

# Print all project items
Recurse-Project -Action {param($item) "`"$($item.ProjectItem.Name)`" is a $($item.Type)" }

# Function to format all documents based on https://gist.github.com/984353
function Format-Document {
    Recurse-Project -Action { param($item)
        if($item.Type -eq 'Folder' -or !$item.Language) {
            return
        }
        
        $window = $item.ProjectItem.Open('{7651A701-06E5-11D1-8EBD-00A0C90F26EA}')
        if ($window) {
            Write-Host "Processing `"$($item.ProjectItem.Name)`""
            [System.Threading.Thread]::Sleep(100)
            $window.Activate()
            $Item.ProjectItem.Document.DTE.ExecuteCommand('Edit.FormatDocument')
            $Item.ProjectItem.Document.DTE.ExecuteCommand('Edit.RemoveAndSort')
            $window.Close(1)
        }
    }
}

ProjectItem Recursion

function Recurse-Project {
    param(
        [string]$Project,
        [parameter(Mandatory = $true)]$Action
    )
    
    # Convert project item guid into friendly name
    function Get-Type($kind) {
        switch($kind) {
            '{6BB5F8EE-4483-11D3-8BCF-00C04F8EC28C}' { 'File' }
            '{6BB5F8EF-4483-11D3-8BCF-00C04F8EC28C}' { 'Folder' }
            default { $kind }
        }
    }
    
    # Convert language guid to friendly name
    function Get-Language($item) {
        if(!$item.FileCodeModel) {
            return $null
        }
        
        $kind = $item.FileCodeModel.Language
        switch($kind) {
            '{B5E9BD34-6D3E-4B5D-925E-8A43B79820B4}' { 'C#' }
            '{B5E9BD33-6D3E-4B5D-925E-8A43B79820B4}' { 'VB' }
            default { $kind }
        }
    }
    
    # Walk over all project items running the action on each
    function Recurse-ProjectItems($projectItems, $action) {
        $projectItems | %{
            $obj = New-Object PSObject -Property @{
                ProjectItem = $_
                Type = Get-Type $_.Kind
                Language = Get-Language $_
            }
            
            & $action $obj
            
            if($_.ProjectItems) {
                Recurse-ProjectItems $_.ProjectItems $action
            }
        }
    }
    
    if($Project) {
        $p = Get-Project $Project
    }
    else {
        $p = Get-Project
    }
    
    Recurse-ProjectItems $p.ProjectItems $Action
}

# Statement completion for project names
Register-TabExpansion 'Recurse-Project' @{
    Project = { Get-Project -All | Select -ExpandProperty Name }
}