Question

this is my first time asking a question so bear with me. I am teaching myself powershell by writing a few basic maintenance scripts. My question is in regard to a clean up script I am writing which accepts arguments to determine the target directory and files to delete.

The Problem:

The script accepts an optional argument for a list of file extensions to look for when processing the deletion of files. I am trying to test for the existence of the files prior to actually running the delete. I use test-path with the –include parameter to run the check within a ValidateScript block. It works if I pass in a single file extension or no file extensions, however when I try to pass in more than one file extension it fails.

I have tried using the following variations on the code inside the script:

[ValidateScript({ Test-Path $targetDirChk  -include $_ })]

[ValidateScript({ Test-Path $targetDirChk  -include "$_" })]

[ValidateScript({ Test-Path $targetDirChk  -include ‘$_’ })]

For each of the above possibilities I have run the script from the command line using the following variations for the multi extension file list:

& G:\batch\DeleteFilesByDate.ps1 30 G:\log  *.log,*.ext

& G:\batch\DeleteFilesByDate.ps1 30 G:\log  “*.log, *.ext”

& G:\batch\DeleteFilesByDate.ps1 30 G:\log  ‘*.log, *.ext’

Example of the error message:

chkParams : Cannot validate argument on parameter 'includeList'. The " Test-Path $targetDirChk -include "$_" " validation script for the argument with value "*.log, *.ext" did not return true. Determine why the validation script failed and then try the command again.
At G:\batch\DeleteFilesByDate.ps1:81 char:10
+ chkParams <<<<  @args
    + CategoryInfo          : InvalidData: (:) [chkParams], ParameterBindingValidationException
    + FullyQualifiedErrorId : ParameterArgumentValidationError,chkParams

The full script is below. I have not yet added the actual code to delete files, because I am still working on accepting and validating the arguments passed in.

I have searched google and stackoverflow but I have not found a solution to this particular problem. I assume I am either doing something wrong with the code, or there is a better way to accomplish what I want to do.

Note:
I should mention that I also tried running the test-path with multiple file extensions outside of the script with no problems:

PS G:\batch\powershell> test-path G:\log\* -include *.log

True

PS G:\batch\powershell> test-path G:\log\* -include *.log, *.ext

True

Script:

# Check that the proper number of arguments have been supplied and if not provide usage statement.
# The first two arguments are required and the third is optional.
if ($args.Length -lt 2 -or $args.Length -gt 3 ){
    #Get the name of the script currently executing.
    $ScriptName = $MyInvocation.MyCommand.Name
    $ScriptInstruction = @"

    usage: $ScriptName <Number of Days> <Directory> [File Extensions]

    This script deletes files from a given directory based on the file date.

    Required Paramaters:

    <Number of Days>:   
    This is an integer representing the number of days worth of files 
    that should be kept. Anything older than <Number of Days> will be deleted.

    <Directory>:        
    This is the full path to the target folder.

    Optional Paramaters:

    [File Extensions]   
    This is the set of file extensions that will be targeted for processing. 
    If nothing is passed all files will be processed.
"@  
    write-output $ScriptInstruction
    break
}
#Function to validate arguments passed in.
function chkParams()
{
    Param(
    [Parameter(Mandatory=$true,
        HelpMessage="Enter a valid number of days between 1 and 999")]

    #Ensure the value passed is between 1 and 999.
    #[ValidatePattern({^[1-9][0-9]{0,2}$})]
    [ValidateRange(1,999)]
    [Int]
    $numberOfDays,

    [Parameter(Mandatory=$true,
        HelpMessage="Enter a valid target directory.")]
    #Check that the target directory exists.
    [ValidateScript({Test-Path $_ -PathType 'Container'})] 
    [String]
    $targetDirectory,   

    [Parameter(Mandatory=$false,
        HelpMessage="Enter the list of file extensions.")]  
    #If the parameter is passed, check that files with the passed extension(s) exist.   
    [ValidateScript({ Test-Path $targetDirChk -include "$_" })]
    [String]
    $includeList
    )
    #If no extensions are passed check to see if any files exist in the directory.
    if (! $includeList ){
        $testResult = Test-path $targetDirChk
        if (! $testResult ){
            write-output "No files found in $targetDirectory"
            exit
        }
    } 
}
#
if ($args[1].EndsWith('\')){
    $targetDirChk = $args[1] + '*'
} else {
    $targetDirChk = $args[1] + '\*'
}       
chkParams @args

Answer 1

-Include on Test-Path is a string[]. You probably want to mirror that definition:

[ValidateScript({ Test-Path $targetDirChk -include $_ })]
[String[]]
$includeList

And drop the "" from there because they will force the argument to be a string and thus trying to match a file that looks like `foo.log blah.ext.

You also have to either put parentheses around that argument when calling the function or remove the space.