为什么在停止excel进程后出现“远程过程调用失败”错误？

Question

我有以下代码将excel工作表转换为csv文件。如果csv文件不存在/或已经存在但尚未使用（例如在excel中打开），则脚本会成功生成csv文件（如果已经存在，则将其覆盖）！

但是，如果在excel中打开了csv文件，那么我会得到一个错误消息“无法访问csv文件”，这是因为它已被excel使用（打开时）。我知道这是100％的原因，因为如果我在记事本中打开了现有的csv文件，则脚本仍会覆盖csv文件，并且运行成功。

所以我尝试实现自动解析，即Get-Process 'exce[l]' | Stop-Process -Force，尽管它确实停止了该过程（关闭excel），但我仍然遇到另一个错误：

Convert-ExcelSheetsToCsv : Failed to save csv! Path: 'C:\Users\Documents\Folder1\CSV_Files\COS.csv'. The remote
procedure call failed. (Exception from HRESULT: 0x800706BE)

Convert-ExcelSheetsToCsv : Failed to save csv! Path: 'C:\Users\Documents\Folder1\CSV_Files\.csv'. The RPC server is
unavailable. (Exception from HRESULT: 0x800706BA)

经过一番研究，我禁用了我的COM-Excel插件，再次运行了脚本，但仍然再次出现异常...

为什么？

$currentDir = $PSScriptRoot

$csvPATH = Join-Path -Path $currentDir -ChildPath CSV_Files
New-Item -ItemType Directory -Force -Path $csvPATH | out-null

function Convert-ExcelSheetsToCsv {
    param(
        [Parameter(Mandatory, ValueFromPipelineByPropertyName, Position=1)]
        [ValidateNotNullOrEmpty()]
        [Alias('FullName')]
        [string]$Path,
        [Parameter(Mandatory = $false, Position=0)]
        [bool]$AppendFileName,
        [Parameter(Mandatory = $false, Position=2)]
        [bool]$ExcludeHiddenSheets,
        [Parameter(Mandatory = $false, Position=3)]
        [bool]$ExcludeHiddenColumns
    )
    Begin {
        $excel = New-Object -ComObject Excel.Application -Property @{
            Visible       = $false
            DisplayAlerts = $false
        }
    }
    Process {
        #$root = Split-Path -Path $Path
        $filename = [System.IO.Path]::GetFileNameWithoutExtension($Path)
        $workbook = $excel.Workbooks.Open($Path)

        foreach ($worksheet in ($workbook.Worksheets | Where { <# $_.Visible -eq -1 #> $_.Name -ne 'Security' -and $_.Name -ne 'Notes' })) {        
            if($ExcludeHiddenColumns) {
                $ColumnsCount = $worksheet.UsedRange.Columns.Count
                for ($i=1; $i -le $ColumnsCount; $i++)
                {
                    $column = $worksheet.Columns.Item($i).EntireColumn #$worksheet.sheets.columns.entirecolumn.hidden=$true
                    if ($column.hidden -eq $true)
                    {   
                        $columnname = $column.cells.item(1,$i).value2

                        if ($worksheet.Visible -eq 0) #worksheet hidden
                        {
                            "`r`nHidden column [{0}] found in hidden [{1}] worksheet. Deleting..." -f $columnname, $($worksheet.name)
                        }
                        else {
                            "`r`nHidden column [{0}] found in [{1}] worksheet. Deleting..." -f $columnname, $($worksheet.name)
                        }

                        try {
                            $column.Delete() | out-null

                            "`r`nHidden column [{0}] was Deleted! Proceeding with Export to CSV operation...`r`n" -f $columnname
                        }
                        catch {
                            Write-Error -Message "`r`nFailed to Delete hidden column [$columnname] from [$($worksheet.name)] worksheet! $PSItem"
                            #$_ | Select *
                        }

                        #$i = $i - 1
                    }
                }
            }

            if ($ExcludeHiddenSheets) {
                if ($worksheet.Visible -eq -1) #worksheet visible
                {
                    $ws = $worksheet
                }
            }
            else {
                $ws = $worksheet
            }

            if ($AppendFileName) {
                $name = Join-Path -Path $csvPATH <# $root #> -ChildPath "${filename}_$($ws.Name).csv"
            }
            else {
                $name = Join-Path -Path $csvPATH <# $root #> -ChildPath "$($ws.Name).csv"
            }

            try {
                $ws.SaveAs($name, 6) #6 to ignore formatting and convert to pure text, otherwise, file could end up containing rubbish
            } 
            catch {
                if ($error[0].ToString().Contains("Cannot access"))
                {
                    "`r`n'{0}' is currently in use.`r`n Attempting to override usage by trying to stop Excel process..." -f $name

                    try {
                        #Only 'excel' will be matched, but because a wildcard [] is used, not finding a match will not generate an error.
                        #https://stackoverflow.com/a/32475836/8397835

                        Get-Process 'exce[l]' | Stop-Process -Force

                        "`r`nExcel process stopped! Saving '{0}' ..." -f $name

                        $ws.SaveAs($name, 6)
                    }
                    catch {
                        Write-Error -Message "Failed to save csv! Path: '$name'. $PSItem"
                    }
                }
                else {
                    Write-Error -Message "Failed to save csv! Path: '$name'. $PSItem"
                }
            }
        }
    }
    End {
        $excel.Quit()
        $null = [System.Runtime.InteropServices.Marshal]::ReleaseComObject($excel)
    }
}

Get-ChildItem -Path $currentDir -Filter *.xlsx | Convert-ExcelSheetsToCsv -AppendFileName 0 -ExcludeHiddenSheets 1 -ExcludeHiddenColumns 1 #0 for false, so that filename of excel file isnt appended, and only sheet names are the names of the csv files

Answer 1

这是因为excel对象最终也被破坏了。正确的方法是在实例化excel对象之前结束进程：

Begin {
    Get-Process 'exce[l]' | Stop-Process -Force