PowerShell DataTable 删除空行

Question

我在使用 Excel.Application 对象时偶然发现了一些 (DCOM) 问题。因此，我使用AccessDatabaseEngine_x64 中的OleDbConnection 和OleDbCommand 对象重写了读取Excel 文件的函数。所以服务器上不用再安装MS Office了，我觉得也比较靠谱。

它工作得很好，但唯一缺少的是我似乎无法弄清楚如何从函数的输出中删除空行。我知道可以通过使用$DataTable[0].Delete() 来完成，但我不知道如何确定一个完整的行是否为空。因为它的大小可能因输入而异。

XLSX-文件示例：

Name     | Sir name
Bob Lee  | Swagger
         |
Jake     | Thornton

在上面的示例中，我希望只输出 2 行（或 3 行，具体取决于 $Header 开关），但我不想在输出中看到空行。

我找到了另一种语言的 solution，但我无法将其翻译成 PowerShell。

代码：

Function Import-Excel {
    [CmdletBinding()]
    Param (
        [parameter(Mandatory=$true,Position=0)]
        [ValidateScript({Test-Path $_ -PathType Leaf})]
        [String]$FileName, 
        [parameter(Mandatory=$true,Position=1)]
        [String]$WorksheetName,
        [Switch]$Header
    )

    Begin {
        # We can't read open XLSX-Files
        Copy-Item -LiteralPath $FileName -Destination $env:TEMP
    }

    Process {
        $OleDbConnection = New-Object 'System.Data.OleDb.OleDbConnection'
        $OleDbCommand    = New-Object 'System.Data.OleDb.OleDbCommand'
        $ConnString = 'Provider=Microsoft.ACE.OLEDB.12.0;Data Source='
        $ConnString += "$env:TEMP\$(Split-Path $FileName -Leaf)"

        if ($header) {
            $ConnString += ';Extended Properties="Excel 12.0;HDR=YES;IMEX=1";'
        }
        else {
            $ConnString += ';Extended Properties="Excel 12.0;HDR=NO;IMEX=1";'
        }

        $OleDbConnection.ConnectionString = $ConnString
        $OleDbConnection.Open()

        $OleDbCommand.Connection = $OleDbConnection
        $OleDbCommand.CommandText = "SELECT * FROM [$WorksheetName$]"

        $OleDbAdapter = New-Object "System.Data.OleDb.OleDbDataAdapter"
        $OleDbAdapter.SelectCommand = $OleDbCommand

        $DataTable = New-Object "System.Data.DataTable"
        $OleDbAdapter.Fill($DataTable)

        $OleDbConnection.Close() 
        Write-Output $DataTable
    }
    End {
        Remove-Item "$env:TEMP\$(Split-Path $FileName -Leaf)"
    }
}

感谢您的帮助。

Answer 1

同时为遇到相同问题的任何人找到答案：

Function Import-Excel {
    [CmdletBinding()]
    Param (
        [parameter(Mandatory=$true,Position=0)]
        [ValidateScript({Test-Path -LiteralPath $_ -PathType Leaf})]
        [String]$FileName, 
        [parameter(Mandatory=$true,Position=1)]
        [String]$WorksheetName,
        [Switch]$Header
    )

    Begin {
        # We can't read open XLSX-Files
        Copy-Item -LiteralPath $FileName -Destination $env:TEMP
    }

    Process {
        $OleDbConnection = New-Object 'System.Data.OleDb.OleDbConnection'
        $OleDbCommand    = New-Object 'System.Data.OleDb.OleDbCommand'
        $OleDbAdapter    = New-Object 'System.Data.OleDb.OleDbDataAdapter'
        $DataTable       = New-Object 'System.Data.DataTable'

        $ConnString = 'Provider=Microsoft.ACE.OLEDB.12.0;Data Source='
        $ConnString += "$env:TEMP\$(Split-Path $FileName -Leaf)"

        if ($header) {
            $ConnString += ';Extended Properties="Excel 12.0;HDR=YES;IMEX=1";'
        }
        else {
            $ConnString += ';Extended Properties="Excel 12.0;HDR=NO;IMEX=1";'
        }

        $OleDbConnection.ConnectionString = $ConnString
        $OleDbConnection.Open()

        $OleDbCommand.Connection = $OleDbConnection
        $OleDbCommand.CommandText = "SELECT * FROM [$WorksheetName$]"

        $OleDbAdapter.SelectCommand = $OleDbCommand
        $OleDbAdapter.Fill($DataTable)

        $OleDbConnection.Close()

        # Remove empty lines
        $Columns = $DataTable.Columns.Count
        $Rows    = $DataTable.Rows.Count

        for ($r = 0; $r -lt $Rows; $r++) {    
            $Empty = 0
             for ($c = 0; $c -lt $Columns; $c++) {

                if ($DataTable.Rows[$r].IsNull($c)) {
                    $Empty++
                }
             }
             if ($Empty -eq $Columns) {
                # Mark row for deletion:
                $DataTable.Rows[$r].Delete()
             }
        }
        # Delete marked rows:
        $DataTable.AcceptChanges()

        Write-Output $DataTable
    }

    End {
        Remove-Item "$env:TEMP\$(Split-Path $FileName -Leaf)"
    }
}