New-FolderWatcher.ps1

function New-FolderWatcher
{
param(
    [Parameter(Mandatory=$true, ValueFromPipelineByPropertyName=$True)]
    $Path,
    [Parameter(Mandatory=$false, ValueFromPipelineByPropertyName=$True)]
    [hashtable] $Events ,
    [Parameter(Mandatory=$false, ValueFromPipelineByPropertyName=$True)]
    $MessageData = "",
    [Parameter(Mandatory=$false, ValueFromPipelineByPropertyName=$True)]    
    [switch] $IncludeSubdirectories
)

PROCESS
{
    if (test-path $Path)
    {
        $watcher = New-Object System.IO.FileSystemWatcher 
        $watcher.Path = $Path
        $watcher.IncludeSubdirectories = $IncludeSubdirectories
        $watcher.EnableRaisingEvents = $true 
        
        $SupportedEvents = $watcher | Get-Member | where {$_.membertype -eq 'Event' }
        $DefaultAction =  { write-host "$($event.SourceIdentifier) '$($eventArgs.FullPath)'" }
        
        if (!$Events)
        {
            $Events = @{}
            $SupportedEvents | ForEach-Object {
                $Events.Add($_.Name, $DefaultAction)
            }
        }
        $Events.Keys | ForEach-Object {
            $EventName = $_
            $Action = $Events[$_]
            $SourceIdentifier = "FileSystemWatcher.$EventName"
            if ($action -is [scriptblock])
            {
                Remove-Event -SourceIdentifier $SourceIdentifier -ErrorAction SilentlyContinue
                Unregister-Event -SourceIdentifier $SourceIdentifier -ErrorAction SilentlyContinue
                
                Register-ObjectEvent -InputObject $watcher -EventName $EventName -SourceIdentifier $SourceIdentifier -Action $Action -MessageData $MessageData
            }
        }
    }
} #end Process

} #end Function

#New-FolderWatcher -Path "C:\temp\watch"

<#
New-FolderWatcher -Path "C:\temp\watch" -Events @{
    'Created'  = { write-host "$($event.SourceIdentifier) file $($eventArgs.FullPath)" }
    'Deleted'  = { write-host "$($event.SourceIdentifier) file $($eventArgs.FullPath)" }
    'Disposed' = { write-host "$($event.SourceIdentifier) file $($eventArgs.FullPath)" }
    'Error'    = { write-host "$($event.SourceIdentifier) file $($eventArgs.FullPath)" }
    'Renamed'  = { write-host "$($event.SourceIdentifier) file $($eventArgs.FullPath)" }
}
#>