PowerShell 5.1 で Windows.Data.Pdf.PdfDocument.PageCount を取得

型[Windows.Data.Pdf.PdfDocument]が見つかるかの確認

# PowerShell 5.1, Windows 11 (2025年4月頃)

$str = 'Windows.Data.Pdf.PdfDocument, Windows.Data, Version=255.255.255.255, Culture=neutral, PublicKeyToken=null, ContentType=WindowsRuntime'
[System.Type]::GetType($str).AssemblyQualifiedName | Write-Host -ForegroundColor DarkYellow
#=> Windows.Data.Pdf.PdfDocument, Windows.Data, Version=255.255.255.255, Culture=neutral, PublicKeyToken=null, ContentType=WindowsRuntime

WindowsRuntimeSystemExtensions.AsTaskメソッドに関連して[System.WindowsRuntimeSystemExtensions].GetMethods()の確認

# PowerShell 5.1, Windows 11 (2025年4月頃)

Set-StrictMode -Version Latest
Add-Type -AssemblyName System.Runtime.WindowsRuntime

$mInfos = [System.WindowsRuntimeSystemExtensions].GetMethods()

$psObjs = [PSObject[]]::new($mInfos.Length)
for ($i = 0; $i -lt $psObjs.Length; $i++) {
    $psObjs[$i] = [PSObject]::new()
}

$numParamsMax = 0

for ($i = 0; $i -lt $psObjs.Length; $i++) {
    $psObjs[$i] | Add-Member -NotePropertyName "Name" -NotePropertyValue $mInfos[$i].Name
    $psObjs[$i] | Add-Member -NotePropertyName "ReturnType" -NotePropertyValue $mInfos[$i].ReturnType.ToString()
    $pInfos = $mInfos[$i].GetParameters()
    $psObjs[$i] | Add-Member -NotePropertyName "NumParams" -NotePropertyValue $pInfos.Length
    for ($k = 0; $k -lt $pInfos.Length; $k++) {
        $psObjs[$i] | Add-Member -NotePropertyName $("ParameterType" + $k.ToString("00")) -NotePropertyValue $pInfos[$k].ParameterType.Name
    }
    $numParamsMax = [System.Math]::Max($pInfos.Length, $numParamsMax)
}

$propNamesParameterType = [string[]]::new($numParamsMax)
for ($i = 0; $i -lt $propNamesParameterType.Length; $i++) {
    $propNamesParameterType[$i] = "ParameterType" + $i.ToString("00")
}

$psObjs | Select-Object -Property $(@("Name", "ReturnType", "NumParams") + $propNamesParameterType) | Out-GridView

PDFのページ数を取得

# PowerShell 5.1, Windows 11 (2025年4月頃)

$ErrorActionPreference = [System.Management.Automation.ActionPreference]::Stop
$VerbosePreference = [System.Management.Automation.ActionPreference]::Continue
Set-StrictMode -Version Latest

$filePath = "${env:USERPROFILE}\Desktop\test.pdf"
$fStream = [System.IO.File]::OpenRead($filePath)
Add-Type -AssemblyName System.Runtime.WindowsRuntime
$raStream = [System.IO.WindowsRuntimeStreamExtensions]::AsRandomAccessStream($fStream)

$null = [Windows.Data.Pdf.PdfDocument, Windows.Data, ContentType = WindowsRuntime]
$iAsyncOpPdfDoc = [Windows.Data.Pdf.PdfDocument]::LoadFromStreamAsync($raStream)

Add-Type -AssemblyName System.Runtime.WindowsRuntime

# メソッド名が AsTask であるものを選択
$miAsTasks = [System.Reflection.MethodInfo[]]@(
    [System.WindowsRuntimeSystemExtensions].GetMethods() | Where-Object { $_.Name -eq "AsTask" }
)

# パラメーターが IAsyncOperation<TResult> だけのものを選択
$miAsTaskIAsyncOpGen = [System.Reflection.MethodInfo](
    $miAsTasks | Where-Object {
        $paramInfos = $_.GetParameters()
        if ($paramInfos.Length -eq 1) {
            $paramInfos[0].ParameterType.Name -eq 'IAsyncOperation`1'
        }
    }
)

# 戻り値とパラメーターを確認
$miAsTaskIAsyncOpGen.ReturnType.ToString() | Write-Verbose
#=> 詳細: System.Threading.Tasks.Task`1[TResult]
$miAsTaskIAsyncOpGen.GetParameters() | ForEach-Object { $_.ParameterType.ToString() | Write-Verbose }
#=> 詳細: Windows.Foundation.IAsyncOperation`1[TResult]

# MakeGenericMethod
$miAsTaskIAsyncOpPdfDoc = $miAsTaskIAsyncOpGen.MakeGenericMethod([System.Type[]]@([Windows.Data.Pdf.PdfDocument]))

# 戻り値とパラメーターを確認
$miAsTaskIAsyncOpPdfDoc.ReturnType.ToString() | Write-Verbose
#=> 詳細: System.Threading.Tasks.Task`1[Windows.Data.Pdf.PdfDocument]
$miAsTaskIAsyncOpPdfDoc.GetParameters() | ForEach-Object { $_.ParameterType.ToString() | Write-Verbose }
#=> 詳細: Windows.Foundation.IAsyncOperation`1[Windows.Data.Pdf.PdfDocument]

# Task<PdfDocument> を取得
$taskPdfDoc = $miAsTaskIAsyncOpPdfDoc.Invoke($null, @($iAsyncOpPdfDoc))

$taskPdfDoc.Wait()

# Task<PdfDocument>.Result
$pdfDoc = $taskPdfDoc.Result

# PDFのページ数
$pdfDoc.PageCount

$fStream.Dispose()