Powershell Change path in variable - powershell

Question

i need you help again :D
I have created a function to put the error logs in a file who take the name of my script (i call multiples scripts so it's very helpful), here is my function :
function ExportLog{
$path = Get-Location
$LogFile = [io.path]::ChangeExtension($MyInvocation.ScriptName,"log")
Write-Host $LogFile
$timestamps = Get-Date
$string_err = $_ | Out-String
$ExportError = "[" + $timestamps.DateTime + "]`n" + $string_err + "`n"| Out-File -FilePath $LogFile -Append
Read-Host “Appuyez sur ENTRER pour quitter...”}
This works fine but the log file created or edited is in the path of my script.
My question is how can i add \log\ in the path who is in my variable $LogFile ?
I tried to use Join-Path, but it just add path like this : C:\import\Modif_CSV.log\Logs ... I wan't to add the Logs folder before the name of the file ^^
Ty for help :)

Answer 1

You can split the current script filename from the full path and change the extension with:
$LogFileName = [IO.Path]::ChangeExtension((Split-Path $PSCommandPath -Leaf), 'log')
Next combine the current script path with the subfolder 'log' and with the new filename
$LogFullName = [IO.Path]::Combine($PSScriptRoot, 'log', $LogFileName)

Answer 2

Theo's helpful answer shows a .NET API-based solution that works in both Windows PowerShell and PowerShell (Core) 7+.
Here's a PowerShell (Core) 7+ solution that showcases new features (relative to Windows PowerShell):
$dir, $name = $PSCommandPath -split '\\', -2
Join-Path $dir log ((Split-Path -LeafBase $name) + '.log')
-split '\\', -2 splits the path into two strings by \: the last \-separated token, preceded by everything before the last \, thereby effectively splitting a file path into its directory path and file name. That is, -split now accepts a negative number as the count of tokens to return, with -$n meaning: return $n-1 tokens from the right of the input string (albeit in left-to-right order), and save any remaining part of the string in the return array's first element; e.g., 'a/b/c/d' -split '/', -3 yields 'a/b', 'c', 'd'
Split-Path -LeafBase returns a file path's file-name base, i.e. the file name without its extension.
Join-Path now accepts an open-ended number of child paths to join to the parent path; e.g., Join C:\ dir subdir now works to create C:\dir\subdir, whereas in Windows PowerShell you had to nest calls: Join-Path (Join-Path C:\ dir) subdir
Note: It would be handy if Split-Path supported returning all components of a given path in a single operation; GitHub issue #6606 proposes an -All switch that returns an object whose properties reflect all the constituent parts of the path, which would enable the following simplified solution:
# WISHFUL THINKING, as of PowerShell 7.2
$pathInfo = Split-Path -All $PSCommandPath
Join-Path $pathInfo.Parent log ($pathInfo.LeafBase + '.log')