Rename Files To Time Last Modified

A PowerShell Script which copies files from DIR_IN to DIR_OUT, while renaming each file to the time said file was last modified.

#My Working Directories
$DIR_IN = 'C:\alpha\input'
$DIR_OUT = 'C:\alpha\output'

#Loop Over DIR_IN
$Items = Get-ChildItem -Path $DIR_IN
ForEach ($old_name in $items)
    {
    
    #Assemble New Name
    $base = $old_name.LastWriteTime
    $base = $base.ToString("yyyy-MM-dd-hh-mm-ss")
    $base += '-BrettRants'
    $ext = $old_name.Extension
    $new_name = $base + $ext

    #Path In and Out
    $path_in = JOIN-PATH $DIR_IN $old_name
    $path_out = JOIN-PATH $DIR_OUT $new_name
   
    #A Bit Of Feedback
    $path_in
    $path_out
    
    #Make The New Copy
    Copy-Item $path_in $path_out

    }

To work, the above would need to be saved as a Powershell Script and run from file. And to do that, the Execution Policy needs to be reset:

Set-ExecutionPolicy Bypass -Scope Process

The only part of the above which is the least bit interesting to me is the portion entitled #Assemble New Name, so that's the only portion I will discuss further.

• #Assemble New Name
• Shall we comment?
• Yes, we shall.
• $base = $old_name.LastWriteTime
• This extracts a time object from the old file...
  • Meaning, $old_name would have been more accurately called $file_in.
    • Live & Learn!
• $base = $base.ToString("yyyy-MM-dd-hh-mm-ss")
• The time object is converted to a string in the noted format.
• $base += '-BrettRants'
• You may not want this part.
• I do.
• $ext = $old_name.Extension
• It's really handy that PowerShell Items are Complete Objects.
• I'm finding everything to be very robust.
• $new_name = $base + $ext
• And here we have a simple bit of string concatenation.

Bam!

And done!