Powershell 搜索文本文件进行匹配并在行尾添加回车

Question

I am attempting to parse a text file and match set of characters and then add a carriage return at the end of that line to add some spacing. I have tried a number of different ways to do this but haven't been successful. Code sample below results in matching and returning only the lines with the match and doesn't add the carriage line.

[string[]]$arrayFromFile = Get-Content -Path "C:\abc.txt" 
$Return = $arrayFromFile -match 'ghijk' -split "`r"
$Return | Out-File "C:\abc.txt" 

Results:

• ghij
• ghmno
• ghabc

What I want to do is below. Find the results "gh" and add a carriage return at the end of that line while keeping all of the content in the text file.

From:

• abcdefmno
• abcdefpqr
• ghij
• abcdef
• ghmno
• abcdef
• abcdef
• ghabc
• mnop

To:

• abcdefmno
• abcdefpqr
• ghij

• abcdef
• ghmno

• abcdef
• abcdef
• ghabc

• mnop

Thanks for any help!

Answer 1

You can achieve this in a single pipeline:

Get-Content -Path "C:\abc.txt" | foreach {
   $_
   if ($_ -like "gh*") {
       "" # additional empty line
   }
} | Out-File "C:\abc.txt" 

Instead of inserting any line breaks or carriage returns, outputting an empty line (empty string) is enough. The line breaks will be automatically handled by Out-File .

Instead of -like "gh*" (to satisfy the requirement of your example), you can of course do -match <your regex> or whatever you like.

Answer 2

We combine all the steps in a switch statement with the -Regex and -File parameters. It will read the file line by line, we match against letters gh and on those matching lines add a blank line to the output. All this is captured in $return and then we use Set-Content to write it back out.

$file = 'c:\abc.txt'

$return = switch -Regex -File $file {
    gh {$_; ''}
    default {$_}
}

$return | Set-Content $file -Encoding UTF8

Note Out-File can be problematic with encodings thus I changed it to Set-Content