问题描述
InputObject : created_at : Tue Sep 24 02:31:26 +0000 2020
SideIndicator : =>
InputObject : text : CH#66551 by @Test: Testing this script to see if it works
SideIndicator : =>
InputObject : created_at : Tue Sep 24 00:27:01 +0000 2020
SideIndicator : =>
InputObject : text : CH#34330 by Test: Fixed every thing that is able to breathe
SideIndicator : =>
InputObject : created_at : Tue Sep 22 02:31:26 +0000 2020
InputObject : text : CH#66551 by @User2: Fixing stuff
InputObject : created_at : Tue Sep 22 00:27:01 +0000 2020
InputObject : text : CH#34330 by User1: Seeing if it works
InputObject : created_at : Mon Sep 21 15:54:20 +0000 2020
InputObject : text : CH#34294 by User1: Trying to find a workaround
InputObject : created_at : Mon Sep 21 15:29:13 +0000 2020
InputObject : text : CH#34291 by User3: Doing something else
InputObject : created_at : Mon Sep 21 15:03:15 +0000 2020
InputObject : text : CH#34286 by User3: Running around
InputObject :
InputObject :
我想删除此.txt文件中最后一个“ SideIndicator：=>”之后的所有内容 自从我是PowerShell新手以来，就非常感谢您的帮助。
解决方法
您可以简单地执行以下操作：
(Get-Content file.txt -Raw | Select-String -pattern '(?s).*SideIndicator : =>').Matches.Value |
Set-Content newfile.txt
说明：
使用-Raw可以将文件作为单个字符串读取。这使单行模式(?s)可以有效地工作。单行模式允许.匹配换行符，从而可以轻松地跨多行匹配批量字符。
由于Select-String返回MatchInfo个对象，因此访问Value属性的Matches属性只会返回匹配的文本。
对不起，我错过了您的要求并重写了代码
也许不是最优雅的方式（我是新手...），但是我已经对其进行了测试，并且可以根据您的要求进行操作：
$path="C:\test\test.txt" #contains the data you ve shown in your question
$newPath="C:\test\test1.txt" #servs as a testfile to see if the data is correct
$end=(Get-Content -Path $path -Raw).LastIndexOf("SideIndicator : =>")
$length=("SideIndicator : =>").Length
(Get-Content -Path $path -Raw).Substring(0,$end+$length) | Add-Content -Path $newPath
这是一种获得我认为想要的方法。由于您未完全指定所需的内容，因此我抓取了与SideIndicator关联的两行，并从中建立了[PSCustomObject]。如果您需要较少的信息，请根据需要修改该部分。 [咧嘴]
它做什么...
- 无法读取文本文件
准备使用真实数据执行此操作时，请用对#region/#endregion的调用替换整个Get-Content块。 - 设置目标以决定保留什么
- 反复浏览
- 测试目标
- 如果找到，则会构建一个
[PSCustomObject]来容纳所需的行 - 如果未找到，则不执行任何操作
- 将
PSCO发送到$Result集合 - 在屏幕上显示
代码...
#region >>> fake reading in a text file
# in real life,use Get-Content
$InStuff = @'
InputObject : created_at : Tue Sep 24 02:31:26 +0000 2020
SideIndicator : =>
InputObject : text : CH#66551 by @Test: Testing this script to see if it works
SideIndicator : =>
InputObject : created_at : Tue Sep 24 00:27:01 +0000 2020
SideIndicator : =>
InputObject : text : CH#34330 by Test: Fixed every thing that is able to breathe
SideIndicator : =>
InputObject : created_at : Tue Sep 22 02:31:26 +0000 2020
InputObject : text : CH#66551 by @User2: Fixing stuff
InputObject : created_at : Tue Sep 22 00:27:01 +0000 2020
InputObject : text : CH#34330 by User1: Seeing if it works
InputObject : created_at : Mon Sep 21 15:54:20 +0000 2020
InputObject : text : CH#34294 by User1: Trying to find a workaround
InputObject : created_at : Mon Sep 21 15:29:13 +0000 2020
InputObject : text : CH#34291 by User3: Doing something else
InputObject : created_at : Mon Sep 21 15:03:15 +0000 2020
InputObject : text : CH#34286 by User3: Running around
InputObject :
InputObject :
'@ -split [System.Environment]::NewLine
#endregion >>> fake reading in a text file
$Target = 'SideIndicator'
$Result = foreach ($Index in 0..$InStuff.GetUpperBound(0))
{
if ($InStuff[$Index] -match $Target)
{
[PSCustomObject]@{
IO_Line = $InStuff[$Index -1]
SI_Line = $InStuff[$Index]
}
}
} # end >>> foreach ($Index in 0..$InStuff.GetUpperBound(0))
$Result
输出...
IO_Line SI_Line
------- -------
InputObject : created_at : Tue Sep 24 02:31:26 +0000 2020 SideIndicator : =>
InputObject : text : CH#66551 by @Test: Testing this script to see if it works SideIndicator : =>
InputObject : created_at : Tue Sep 24 00:27:01 +0000 2020 SideIndicator : =>
InputObject : text : CH#34330 by Test: Fixed every thing that is able to breathe SideIndicator : =>
一种替代方法是使用LastIndexOf()：
$txt = Get-Content -Path 'TheFullPathOfTheTxtFile' -Raw
$lastIndex = $txt.LastIndexOf("SideIndicator")
if ($lastIndex -ge 0) {
# create a new text file here
# $txt.Substring(0,($lastIndex + 18)) | Set-Content -Path 'TheFullPathOfThe_NEW_TxtFile'
# for demo,just output on console screen
$txt.Substring(0,($lastIndex + 18)) # 18 = length of "SideIndicator : =>"
}
或使用Select-String：
$txt = Get-Content -Path 'TheFullPathOfTheTxtFile' -Raw
$txt.Substring(0,($txt | Select-String -Pattern '(?m)^SideIndicator' -AllMatches).Matches[-1].Index + 18)
我必须感谢你们所有人花时间帮助我。昨天我实际上找到了我测试过的（另一个）解决方案（compare-object left or right side only），效果很好。希望也能尝试您的建议;）