Function Process-Xsl {
  param (
    [Parameter(ValueFromPipeline=$true)][string] $SourceFilePath
  )
  process {
    $xslt.Transform($SourceFilePath, [io.Path]::ChangeExtension($SourceFilePath, ".htm"));
  }
}
cls;
$xslt = New-Object Xml.Xsl.XslCompiledTransform;
$xslt.Load("D:\Trash\xsl\myxslt.xsl");
ls "D:\Trash\xml" | Select -exp Fullname | Process-Xsl

$xslt = New-Object Xml.Xsl.XslCompiledTransform;
$xslt.Load("D:\Trash\xsl\myxslt.xsl");
ls "D:\Trash\xml" | ?{ !$_.PSIsContainer } | Select -exp Fullname |
%{$xslt.Transform($_, [io.Path]::ChangeExtension($_, ".htm"))}

cls;
$srcFolder = "D:\Trash"
$dstFolder = "D:\Trash\1"
# Saxon stuff
Add-Type -Path "D:\Program Files\Saxonica\SaxonHE9.5N\bin\saxon9he-api.dll"
$proc = New-Object Saxon.Api.Processor
$docBuilder = $proc.NewDocumentBuilder()
$xslCompiler = $proc.NewXsltCompiler()
$xslCompiler.BaseUri = New-Object Uri("http://www.w3.org/1999/xhtml")
$xsltExec = $xslCompiler.Compile((New-Object Uri("D:\XSL\myxsl.xsl")))
$xslTrans = $xsltExec.Load()
$serializer = $proc.NewSerializer()
#---------------------
ls $srcFolder | ?{!$_.PSIsContainer} | Select -exp Fullname |
%{
	$xslTrans.InitialContextNode = $docBUilder.Build((New-Object Uri($_)))
	$serializer.SetOutputFile((Join-Path $dstFolder (Split-Path $_ -Leaf)))
	$xslTrans.Run($serializer)
}
Write-Host "done"