Powershell: resolve path that might not exist?

Question

I\'m trying to process a list of files that may or may not be up to date and may or may not yet exist. In doing so, I need to resolve the full path of an item, even though

Answer 1

You can just set the -errorAction to "SilentlyContinue" and use Resolve-Path

5 >  (Resolve-Path .\AllFilerData.xml -ea 0).Path
C:\Users\Andy.Schneider\Documents\WindowsPowerShell\Scripts\AllFilerData.xml

6 >  (Resolve-Path .\DoesNotExist -ea 0).Path

7 >

Answer 2

function Get-FullName()
{
    [CmdletBinding()]
    Param(
        [Parameter(ValueFromPipeline = $True)] [object[]] $Path
    )
    Begin{
        $Path = @($Path);
    }
    Process{
        foreach($p in $Path)
        {
            if($p -eq $null -or $p -match '^\s*$'){$p = [IO.Path]::GetFullPath(".");}
            elseif($p -is [System.IO.FileInfo]){$p = $p.FullName;}
            else{$p = [IO.Path]::GetFullPath($p);}
            $p;
        }
    }
}

Answer 3

I've found that the following works well enough.

$workingDirectory = Convert-Path (Resolve-Path -path ".")
$newFile = "newDir\newFile.txt"
Do-Something-With "$workingDirectory\$newFile"

Convert-Path can be used to get the path as a string, although this is not always the case. See this entry on COnvert-Path for more details.

Answer 4

I had a similar issue where I needed to find the folder 3 levels up from a folder that does not exist yet to determine the name for a new folder I wanted to create... It's complicated. Anyway, this is what I ended up doing:

($path -split "\\" | select -SkipLast 3) -join "\\"

Answer 5

There is an accepted answer here, but it is quite lengthy and there is a simpler alternative available.

In any recent version of Powershell, you can use Test-Path -IsValid -Path 'C:\Probably Fake\Path.txt'

This simply verifies that there are no illegal characters in the path and that the path could be used to store a file. If the target doesn't exist, Test-Path won't care in this instance -- it's only being asked to test if the provided path is potentially valid.

Answer 6

You want:

c:\path\exists\> $ExecutionContext.SessionState.Path.GetUnresolvedProviderPathFromPSPath(".\nonexist\foo.txt")

returns:

c:\path\exists\nonexists\foo.txt

This has the advantage of working with PSPaths, not native filesystem paths. A PSPAth may not map 1-1 to a filesystem path, for example if you mount a psdrive with a multi-letter drive name.

-Oisin