使用“select-string -pattern”从文件中去除行时的空白第一行

Question

我有一个简单的文本文件，看起来像这样......

A,400000051115,null,null,null,null,null,null,null,20190312,090300,Answer Machine,2019,3,14,10,0
A,400000051117,null,null,null,null,null,null,null,20190312,090300,Confirmed,2019,3,14,10,30
A,400000051116,null,null,null,null,null,null,null,20190312,090300,Answer Machine,2019,3,14,11,0
A,400000051114,null,null,null,null,null,null,null,20190312,090300,Wants to Cancel,2019,3,14,9,0
A,400000051117,null,null,null,null,null,null,null,20190312,091800,SMS Sent,2019,3,14,10,30
A,400000051116,null,null,null,null,null,null,null,20190312,091800,SMS Sent,2019,3,14,11,0
A,400000051115,null,null,null,null,null,null,null,20190312,091800,SMS Sent,2019,3,14,10,0
A,400000051116,null,null,null,null,null,null,null,20190312,093000,Appointment Cancelled/Rescheduled Via SMS,2019,3,14,11,0

我需要将除“发送短信”之外的所有行保存到新文件中。我使用以下......

get-content $SourceFile.FullName | select-string -pattern 'SMS Sent' -notmatch | Out-File $targetFile

为什么在结果文件中我得到一个空白的第一行？

Answer 1

如果将Out-File $targetFile更改为Out-Host或者甚至只省略管道中的最后一个段，您将在控制台输出中看到一个空行。

Get-Content的输出类比是Set-Content，所以如果你将Out-File $targetFile改为Set-Content $targetFile，那么第一行不再是空白。

此外，由于您正在使用CSV文件，您可以使用Import-CSV来读取数据，使用Where-Object来过滤该特定列，尽管需要一些额外的工作来指定标题并从输出文件中省略它们...

$csvHeaders = 1..17 | ForEach-Object -Process { "Column $_" }
$csvHeaders[11] = 'Status'

Import-Csv -Path $SourceFile.FullName -Header $csvHeaders `
    | Where-Object -Property 'Status' -NE -Value 'SMS Sent' `
    | ConvertTo-Csv -NoTypeInformation `
    | Select-Object -Skip 1 `
    | Set-Content $targetFile

...写...

"A","400000051115","null","null","null","null","null","null","null","20190312","090300","Answer Machine","2019","3","14","10","0"
"A","400000051117","null","null","null","null","null","null","null","20190312","090300","Confirmed","2019","3","14","10","30"
"A","400000051116","null","null","null","null","null","null","null","20190312","090300","Answer Machine","2019","3","14","11","0"
"A","400000051114","null","null","null","null","null","null","null","20190312","090300","Wants to Cancel","2019","3","14","9","0"
"A","400000051116","null","null","null","null","null","null","null","20190312","093000","Appointment Cancelled/Rescheduled Via SMS","2019","3","14","11","0"

...到$targetFile。请注意，现在引用所有值。如果您的输入文件确实有标题，那么您可以简单地使用...

Import-Csv -Path $SourceFile.FullName `
    | Where-Object -Property 'Status' -NE -Value 'SMS Sent' `
    | Export-Csv -NoTypeInformation -LiteralPath $targetFile

在任何一种情况下，输出文件都不包含前导空行。