从PowerShell调用Excel VSTO加载项

Question

I have built a VSTO addin for Excel which refreshes a number of PowerQuery workbook connections. So as to avoid an error blocking the main thread causing a "Cartridge not loaded" error I have to run the main code in another thread.

I am doing this via Async method. I also need this to work from the command line so i have exposed the code as a COM visible interface and exposed it in ThisAddIn.vb

 Protected Overrides Function RequestComAddInAutomationService() As Object
        If headless Is Nothing Then
            headless = New HeadlessExec()
        End If
        Return headless
    End Function

This is the interface class

Imports System.Data
Imports System.Runtime.InteropServices
Imports log4net
Imports System.Threading.Tasks

<ComVisible(True)>
Public Interface IHeadlessExec
    Function RefreshDIT() As Task(Of Boolean)
    Function GetState() As String
    Function GetStatusDetails() As String
End Interface


<ComVisible(True)>
<ClassInterface(ClassInterfaceType.None)>
Public Class HeadlessExec
    Implements IHeadlessExec

    Private log As ILog
    Private logdir As String = ThisAddIn.logdir


    Sub New()
        'Initialise here

        log = LogManager.GetLogger("HeadlessExec")
        log.Info("Constructor")

    End Sub

    Public Async Function RefreshDIT() As Task(Of Boolean) Implements IHeadlessExec.RefreshDIT

        log.Debug("Start")
        Dim pq As New PowerQueryRefresh

        Dim ExecDIT As Task(Of Boolean) = pq.ExecRefreshInNewThread()
        Dim status As Boolean = Await ExecDIT
        Return status
        log.Debug("End")

    End Function

Public Function GetState() As String Implements IHeadlessExec.GetState

        log.Debug("Start")
        Dim pq As New PowerQueryRefresh
        GetState = pq.GetState
        log.Debug("GetStateVSTO:" & GetState)
        log.Debug("End")
    End Function

    Public Function GetStatusDetails() As String Implements IHeadlessExec.GetStatusDetails

        log.Debug("Start")
        Dim pq As New PowerQueryRefresh
        GetStatusDetails = pq.GetStatusDetails
        log.Debug("GetStatusDetailsVSTO:" & GetStatusDetails)
        log.Debug("End")
    End Function

I am calling this from Powershell via COM as follows - the key part is ExecuteVSTOAdd_DITRefresh :-

Function RunVSTOProc() {

    $error.Clear()
    try {
        $FilePath = GetMostRecentFile($BASEDIR)
        OpenExcelWithFile($FilePath)
        $ret = ExecuteVSTOAdd_DITRefresh

    } catch {
        HandleError($_)
    }

    if ($vstostate -eq "Error"){
        CleanUpExcel
        Exit
    }
    if (!$error){
        # Only save it if we have no errrors
        $newname = NewName($FilePath)
        Write-Host "Saving as $newname"
        $workbook.saveAs($newname)
    }     

    CleanUpExcel

    Write-Host "Completed Running DIT"
}

ExecuteVSTOAdd_DITRefresh

Function ExecuteVSTOAdd_DITRefresh(){


    try {
        $DITAddin = $global:excel.COMAddins.Item("DITUtility")
        Write-Host "Addin $($DITAddin.ProgID) is connected"

        $autom = $DITAddin.Object
        $CallProc =  $autom.RefreshDIT()
        Write-Host "DIT Refreshed within VSTO"
        $CallProc
    } Catch {
        HandleError($_)
    }

}

This issue is that when RefreshDIT runs Powershell doesn't wait for it to complete. EDIT :- I had an issue with establishing com automation - NOW - i can see details for $DITAddin and I can see the exposed methods BUT I cannot see the exposed method RefreshDIT - even though i can call it - this one is Async and the others are not Async method. Its also not obvious to me how to call it Async from Powershell so it functions as an Async method. Any pointers?

    $DITAddin | Get-Member


   TypeName: System.__ComObject#{000c033a-0000-0000-c000-000000000046}

Name        MemberType Definition                        
----        ---------- ----------                        
Application Property   IDispatch Application () {get}    
Connect     Property   bool Connect () {get} {set}       
Creator     Property   int Creator () {get}              
Description Property   string Description () {get} {set} 
Guid        Property   string Guid () {get}              
Object      Property   IDispatch Object () {get} {set}   
Parent      Property   IDispatch Parent () {get}         
ProgId      Property   string ProgId () {get}            

$autom | Get-Member


   TypeName: System.__ComObject#{159faa2b-4a8e-3bca-bb69-e2268f06d436}

Name             MemberType Definition                
----             ---------- ----------                
GetState         Method     string GetState ()        
GetStatusDetails Method     string GetStatusDetails ()

If I run

$CallProc =  $autom.RefreshDIT()


       $CallProc | Get-Member


   TypeName: System.__ComObject

Name                      MemberType Definition                                                     
----                      ---------- ----------                                                     
CreateObjRef              Method     System.Runtime.Remoting.ObjRef CreateObjRef(type requestedType)
Equals                    Method     bool Equals(System.Object obj)                                 
GetHashCode               Method     int GetHashCode()                                              
GetLifetimeService        Method     System.Object GetLifetimeService()                             
GetType                   Method     type GetType()                                                 
InitializeLifetimeService Method     System.Object InitializeLifetimeService()                      
ToString                  Method     string ToString

()

There is no Run() method and if I try and execute it i get

    $CallProc.Run()
    Method invocation failed because [System.__ComObject] does not contain a method named 'Run'.
    At line:1 char:1
    + $CallProc.Run()
    + ~~~~~~~~~~~~~~~
        + CategoryInfo          : InvalidOperation: (:) [], RuntimeException
        + FullyQualifiedErrorId : MethodNotFound


That failed with ERROR ExecuteVSTOAdd_DITRefresh  : 
RunDIT_VSTO.ps1:164 char:9
+         [System.Threading.Tasks.Task]$tskRefreshDIT = $autom.RefreshD ...
+         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : MetadataError: (:) [], ArgumentTransformationMetadataException

Answer 1

Solved the problem. The Async method wasn't displaying in Powershell when performing a Get-Member on the object but the NON Async methods were.

I already had a an async function with an Await statement in VB.NET so i wrapped it a function without the Async modifier and called that:-

This in the main body of the code:-

Public Async Function ExecRefreshInNewThread() As Task(Of Boolean)

    Dim msg As String

    Try
        Dim tasks As New List(Of Tasks.Task)()
        tasks.Add(Task.Run(AddressOf RefreshSequenceOfConnectionsH))
        Await Task.WhenAll(tasks)
        log.Info("Executed without error")
        Return True
    Catch e As Exception
        msg = FormatExceptionMsg(e)
        log.Error(msg)
        Return False
    End Try

End Function


Public Function ExecRefreshInNewThread_v2() As Boolean

    Dim boo As Task(Of Boolean) = ExecRefreshInNewThread()
    Return boo.Result
End Function

This in the interface class:-

Public Function RefreshDITv2() As Boolean Implements IHeadlessExec.RefreshDITv2

        log.Debug("Start")
        Dim pq As New PowerQueryRefresh

        Dim ExecDIT As Boolean = pq.ExecRefreshInNewThread_v2

        Return ExecDIT
        log.Debug("End")

    End Function

Then this worked in Powershell:-

Function ExecuteVSTOAdd_DITRefresh(){


    try {
        $DITAddin = $global:excel.COMAddins.Item("DITUtility")
        Write-Host "Addin $($DITAddin.ProgID) is connected"

        $autom = $DITAddin.Object
        $tskRefreshDIT = $autom.RefreshDITv2()
        Write-Host "DIT Refreshed within VSTO $CallProc"
        $tskRefreshDIT
    } Catch {
        HandleError($_)
    }

}

Now it waits before moving on.

Answer 2

Try using the Wait method of the task from your async RefreshDIT function:

$tskRefreshDIT = $autom.RefreshDIT()
$bolSuccess = $tskRefreshDIT.Run()
$bolSuccess = $task.Wait(60000)

if ($bolSuccess -eq $true) {
    $CallProc
}