Insert data into file based on file name using powershell

Question

I have a powershell script that goes into a files, and for every instance of E:, it will replace it with CBM-FS01|2013-02-03|E:

$filenames = @("C:\SCRIPT\CBM-FS01-E-20130203114114.txt.out")
foreach ($file in $filenames) {
    $outfile = "$file" + ".sql"

    Get-Content $file | Foreach-object {
       $_ -replace "E:","CBM-FS01|2013-02-03|E:" `
    } | Set-Content $outfile
}

If you look close, you can see that I'm getting this information based on the file name. The file name will always be MNEMONIC-MACHINE-DRIVE-YYYMMDDHHMMSS.txt.

Modifying the script for a few files is fine, but I could potentially need to run this on a hundred files! Is there a way using powershell to use the GET-CHILDITEM cmdlet and have powershell automatically perform the -replace based on the different file names?

EDIT: I need to extract parts of the file name, and insert it into the file. For example, for a file CBM-FS01-E-20130203114114.txt, I need to extract the mnemonic-machine (CBM-FS01) and the YYYMMDD (2013-02-03) into the file. Hence

$_ -replace "E:","CBM-FS01|2013-02-03|E:" `

Answer 1

I think this should work, provided those file name patterns are predictable (and I've predicted them correctly)

$filenames = @("C:\SCRIPT\CBM-FS01-E-20130203114114.txt.out")

$regex = '^([^-]+-[^-]+)-([A-Z])-(\d{4})(\d\d)(\d\d).+'

foreach ($file in $filenames) {

    $outfile = "$file" + ".sql"

    $ReplaceString = ($file | Split-Path -leaf) -replace $regex,'$1|$3-$4-$5|$2:'

    Get-Content $file | Foreach-object {
       $_ -replace "E:",$ReplaceString
    } | Set-Content $outfile
}

Answer 2

Not too sure of the question. It sounds like you have a whole pile of files with the same pattern. You can use the -match operator to do some regex comparison.

$pattern = '[a-zA-Z]+-[a-zA-Z]+-E-[0-9]+\.txt'
$files = Get-ChildItem C:\ -Recurse | ? {$_.name -match $pattern}
foreach($file in $files){
    ...
}