Join an array with newline in PowerShell

Question

I have an array of names that I'm trying to join using a new line character. I have the following code

$body = $invalid_hosts -join "`r`n"
$body = "The following files in $Path were found to be invalid and renamed `n`n" + $body

Finally, I send the contents via email.

$From = "[email protected]"
$To = "[email protected]
$subject = "Invalid language files"

Send-MailMessage -SmtpServer "smtp.domain.com" -From $From -To $To -Subject $subject -Body $body

When I receive the message, the line The following files in <filepath> were found to be invalid and renamed has the expected double space, but the contents of $invalid_hosts are all on one line. I've also tried doing

$body = $invalid_hosts -join "`n"

and

$body = [string]::join("`n", $invalid_hosts)

Neither way is working. What do I need to do to make this work?

Answer 1

Pipe the array to the Out-String cmdlet to convert them from a collection of string objects to a single string:

PS> $body = $invalid_hosts -join "`r`n" | Out-String

Answer 2

It is sufficient just pipe to Out-String (see https://stackoverflow.com/a/21322311/52277)

 $result = 'This', 'Is', 'a', 'cat'
 $strResult = $result  | Out-String
 Write-Host $strResult
This
Is
a
cat