PathProcessingWildcards.ps1
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<#
.SYNOPSIS Demonstrates how to write a command that works with paths that allow wildards and must exist. .DESCRIPTION This command also demonstrates how you need to supply a LiteralPath parameter when your Path parameter accepts wildcards. This is in order to handle paths like foo[1].txt. If you pass this path to the Path parameter, it will fail to find this file because "[1]" is interpreted as a wildcard spec e.g it resolves to foo1.txt. The LiteralPath parameter is used in this case as it does not interpret wildcard chars. .EXAMPLE C:\PS> Import-FileWildcard -LiteralPath ..\..\Tests\foo[1].txt -WhatIf This example shows how to use the LiteralPath parameter with a path that happens to use the wildcard chars "[" and "]". #> function Import-FileWildcard { [CmdletBinding(SupportsShouldProcess=$true, DefaultParameterSetName='Path')] param( # Specifies a path to one or more locations. Wildcards are permitted. [Parameter(Mandatory=$true, Position=0, ParameterSetName="Path", ValueFromPipeline=$true, ValueFromPipelineByPropertyName=$true, HelpMessage="Path to one or more locations.")] [ValidateNotNullOrEmpty()] [SupportsWildcards()] [string[]] $Path, # Specifies a path to one or more locations. Unlike the Path parameter, the value of the LiteralPath parameter is # used exactly as it is typed. No characters are interpreted as wildcards. If the path includes escape characters, # enclose it in single quotation marks. Single quotation marks tell Windows PowerShell not to interpret any # characters as escape sequences. [Parameter(Mandatory=$true, Position=0, ParameterSetName="LiteralPath", ValueFromPipelineByPropertyName=$true, HelpMessage="Literal path to one or more locations.")] [Alias("PSPath")] [ValidateNotNullOrEmpty()] [string[]] $LiteralPath ) begin { } process { # Modify [CmdletBinding()] to [CmdletBinding(SupportsShouldProcess=$true, DefaultParameterSetName='Path')] $paths = @() if ($psCmdlet.ParameterSetName -eq 'Path') { foreach ($aPath in $Path) { if (!(Test-Path -Path $aPath)) { $ex = New-Object System.Management.Automation.ItemNotFoundException "Cannot find path '$aPath' because it does not exist." $category = [System.Management.Automation.ErrorCategory]::ObjectNotFound $errRecord = New-Object System.Management.Automation.ErrorRecord $ex,'PathNotFound',$category,$aPath $psCmdlet.WriteError($errRecord) continue } # Resolve any wildcards that might be in the path $provider = $null $paths += $psCmdlet.SessionState.Path.GetResolvedProviderPathFromPSPath($aPath, [ref]$provider) } } else { foreach ($aPath in $LiteralPath) { if (!(Test-Path -LiteralPath $aPath)) { $ex = New-Object System.Management.Automation.ItemNotFoundException "Cannot find path '$aPath' because it does not exist." $category = [System.Management.Automation.ErrorCategory]::ObjectNotFound $errRecord = New-Object System.Management.Automation.ErrorRecord $ex,'PathNotFound',$category,$aPath $psCmdlet.WriteError($errRecord) continue } # Resolve any relative paths $paths += $psCmdlet.SessionState.Path.GetUnresolvedProviderPathFromPSPath($aPath) } } foreach ($aPath in $paths) { if ($pscmdlet.ShouldProcess($aPath, 'Operation')) { # Process each path $aPath } } } end { } } |