Powershell 导入CSV，其中日期列-lt/-gt（dd.MM.YYYY）

我正在编写一个小的PowerShell脚本来处理CSV文件

CSV文件示例：

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如何正确处理此问题？

您必须阅读并注意错误消息。（顺便说一句，向我们展示错误消息。不要只是说它不起作用。这没有帮助。）

所以两个字符串中的一个是错误的。日期看起来还可以，这意味着我们应该看一下，事实上，我们发现没有“yyy”这样的东西。如果我们将其更正为“yyyy”，则它可以工作：

C:\> [DateTime]::ParseExact("23.06.1976", "dd.MM.yyyy", $null)

Wednesday, 23 June 1976 12:00:00 AM

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IIRC的日期格式只有月份是大写的，你试过“dd.MM.yyyy”吗？

Function Start-MyImport {
    #Build the GUI
    [xml]$xaml_ar = @"
<Window
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        Title="Title" Height="164.653" Width="498.907" ResizeMode="NoResize" Topmost="True" WindowStartupLocation="CenterScreen">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="27*"/>
            <ColumnDefinition Width="464*"/>
        </Grid.ColumnDefinitions>
        <Button Name="agerange_go" Content="go!" HorizontalAlignment="Left" Height="23" Margin="334,71,0,0" VerticalAlignment="Top" Width="96" Grid.Column="1"/>
        <CheckBox Name="agerange_before" Content="birthday before:" Grid.Column="1" HorizontalAlignment="Left" Margin="18,76,0,0" VerticalAlignment="Top"/>
        <CheckBox Name="agerange_after" Content="birthday after:" Grid.Column="1" HorizontalAlignment="Left" Margin="18,103,0,0" VerticalAlignment="Top"/>
        <DatePicker Name="dp_before" Grid.Column="1" HorizontalAlignment="Left" Margin="176,71,0,0" VerticalAlignment="Top"/>
        <DatePicker Name="dp_after" Grid.Column="1" HorizontalAlignment="Left" Margin="176,98,0,0" VerticalAlignment="Top"/>

    </Grid>
</Window>
"@

    $reader_ar = (New-Object System.Xml.XmlNodeReader $xaml_ar)
    $Window_ar = [Windows.Markup.XamlReader]::Load($reader_ar)

    $xaml_ar.SelectNodes("//*[@*[contains(translate(name(.),'n','N'),'Name')]]") | ForEach {
        Set-Variable -Name ($_.Name) -Value $Window_ar.FindName($_.Name)
    }

    #Events
    $agerange_go.Add_Click({
        if ($agerange_before.IsChecked) {
           $dp_before = $dp_before.Text 
           if ($dp_before -ne "") {
                Write-Host $dp_before
                Import-Csv my.csv -Delimiter ";" -Encoding UTF8 | 
                    where birthday -as[DateTime]::ParseExact($_."birthday", "dd.MM.YYYY", $null) -lt $dp_before | 
                    Export-Csv CsvFileOut.csv -Delimiter ";" -Encoding UTF8 -NoTypeInfo
           }
        }
        $Window_ar.Close()
        #Lieferant-Repl
    })
    $Window_ar.ShowDialog() | Out-Null
}

Start-MyImport

where birthday -as[DateTime]::ParseExact($_."birthday", "dd.MM.YYYY", $null) -lt $dp_before

C:\> [DateTime]::ParseExact("23.06.1976", "dd.MM.YYYY", $null)
Exception calling "ParseExact" with "3" argument(s): "String was not recognized as a valid DateTime."

C:\> [DateTime]::ParseExact("23.06.1976", "dd.MM.yyyy", $null)

Wednesday, 23 June 1976 12:00:00 AM