Question

I’m in need a script, in PowerShell or batch script, that will do the following.

1. Rename a file to append creation date minus 1 day to the filename.

   For example:

   foo.xlsx (created 7/27/2011)

   foo-2011-07-26.xlsx –note, it’s yesterday’s date.

   Date format isn’t too important as long as it’s there. There will be 10 files (all with the same creation date), so either I can copy and paste the same renaming line for the different files (just rename the filename) or just have the script affect all *.xlsx files in the existing folder.

2. Create a new folder where those files are and name it ‘fooFolder-2011-07-26’ (yesterday’s date).

3. Move those renamed files to that folder.

I only have limited experience with PowerShell. It’s on my todo list of languages to learn..

Answer 1

Here you go. It could be shortened up a lot using aliases and piping and whatnot, but since you’re unfamiliar with Powershell still, I decided to write in a more procedural style for your reading:

function MoveFilesAndRenameWithDate([string]$folderPrefix, [string]$filePattern) {
  $files = Get-ChildItem .\* -include $filePattern
  ForEach ($file in $files) {
    $yesterDate = $file.CreationTime.AddDays(-1).ToString('yyyy-MM-dd')
    $newSubFolderName = '{0}-{1}' -f $folderPrefix,$yesterDate
    if (!(Test-Path $newSubFolderName)) {
      mkdir $newSubFolderName
    }
    $newFileName = '{0}-{1}{2}' -f $file.BaseName,$yesterDate,$file.Extension
    Move-Item $file (Join-Path $newSubFolderName $newFileName)
  }
}

You would paste the above into your Powershell session (place it in your profile). Then you call the function like this:

MoveFilesAndRenameWithDate 'fooFolder' '*.xslx'

I tend to use more aliases and piping than the above function. The first version I wrote was this, and then I separated parts of it to make it more comprehensible to a Powershell newcomer:

function MoveFilesAndRenameWithDate([string]$folderPrefix, [string]$filePattern) {
  gci .\* -include $filePattern |
    % { $date = $_.CreationTime.AddDays(-1).ToString('yyyy-MM-dd')
        mkdir "$folderPrefix-$date" 2>$null
        mv $_ (join-path $newSubFolderName ('{0}-{1}{2}' -f $_.BaseName,$date,$_.Extension))}
}

Edit: Modified both functions to create dated folder for the files that match that date. I considered making a temporary directory and grabbing a single date from the files moved to it, finally renaming the directory after the loop. However, if a day should be missed and files for 2 (or more) days get processed together, there would still be a folder for each day with these, which is more consistent.