recursing folders and renaming files with create date added to filename - powershell

Question

I am very much a newbie to powershell but have figured out some of what I need for a project at work. We have test result files (PDF, XLS. TXT, etc) in folders relating to test locations. Most folders have subfolders with files. The boss has mandated that the test date must be appended to the end of the file name (test_results.pdf -> test_results - 2014-05-06.pdf).
My code does get the creation date and appends it, however it only works on the folders in the source folder, also it is appending the creation date of the folder. I don't mind the date in the folder name if all the files ends up in the correct location. The files in the source subfolders are written to the new sub but without creation date appended.
Any help is greatly appreciated. Here's my code:
$SourceDir= 'C:\modem\'
$targetDir = 'C:\test2\'
set-location -path $sourceDir
$files = get-childitem -recurse
foreach ($file in $files)
{
[string]$strippedFileName =[io.path]::GetFileNameWithoutExtension($file);
[string]$extension = [io.Path]::GetExtension($file);
[string]$crtime=$file.CreationTime.toString(' - yyyy-MM-dd');
[string]$sourceFilePath = $file.DirectoryName;
[string]$DestinationFile = $targetDir + $sourcefilepath.trimstart($sourceDir) + "\" + $strippedFileName +$crtime + $extension;
Copy-Item $file.Fullname -Destination $DestinationFile -recurse -Force
}
Thank you,
tom

Answer 1

It sounds like it doesn't work for the files in the subfolders because you're creating subfolders in the destination directory with different names (date appended), but when you try to copy the files, you're using the original subfolder names in the path to the destination, so you're trying to copy them to locations that don't exist.
If that's the case, you might be wondering, then why do the files from the source subfolders get copied to the corresponding renamed subfolders, but without the date appended? Simple: because if you Copy-Item -Recurse a folder, all the contents get copied. The files in the subfolders aren't being copied individually by your foreach loop; they're being copied all at once by the last line of the loop each time you create a new (renamed) subfolder.
You can solve both problems simultaneously by simply exculding directories from the results of Get-ChildItem.
In PowerShell 1 and 2:
$files = Get-Childitem -Recurse | ?{$_.PSIsContainer}
In PowerShell 3 and up:
$files = Get-Childitem -Recurse -File
Also, it looks like you're coming from a background of .NET programming in a strongly type language (I'm guessing C# based on your accent). PowerShell is dynamically typed; there's no need (and no advantage) to casting all your variables as strings. The assigments will make them strings. Also, you don't need [IO.Path] to get the parts of the filename; they're attributes of the FileInfo objects returned by Get-ChildItem.
You can write you loop like this:
foreach ($file in $files)
{
$strippedFileName = $file.BaseName;
$extension = $file.Extension;
$crtime=$file.CreationTime.toString(' - yyyy-MM-dd');
$sourceFilePath = $file.DirectoryName;
$DestinationFile = $targetDir + $sourcefilepath.TrimStart($sourceDir) + "\" + $strippedFileName +$crtime + $extension;
Copy-Item $file.FullName -Destination $DestinationFile -Recurse -Force
}