设置内容，然后获取内容以某种方式更改内容

Question

PowerShell changes the contents of a text file on Get-Content or the variable on Set-Content .

This is a PowerShell script for compiling a bunch of files and formatting them to a single text file, this part checks if the new file is equal to the old one, but according to the comparison, it never is. I've tried messing with stuff like making the new var be a string array as get-content is.

$files = Get-ChildItem -path "./dir" | Where-Object -FilterScript {$_.Name -match '[A-J]'}

$var = @()
foreach ($file in $files){
    $filePath = "dir\" + $file;
    $fileContent = Get-Content $filepath
    $var += $fileContent
}
$firstLine = '"this" "issen" "da" "first"'
$var1 = '"abc" "def" "12" "6"'
$var2 = '"456" "def" "12" "4"'
$newContent = $firstLine,$var,$var1,$var2
$oldContent = Get-Content './File.txt'

if (-not (Compare-Object $oldContent $newContent)) {
    Write-Host Nothing new.
} else {
    Write-Host Something new
    Set-Content './File.txt' -value $newContent
}
Set-Content './File.txt' -value $newContent
pause

When comparing $newContent to $oldContent which is just $newContent stored and retrieved from a text file they are not identical. They should be, right?

The text files that are gathered from ./dir are like this: a00.txt

a12 bc23 abc

b00.txt

a12 bc23 abg

Answer 1

Your first line $var = "stuff","and","thangs" creates an array (3 strings):

The -eq operator doesn't work like that for comparing object arrays . You can instead use the Compare-Object cmdlet:

if (-not (Compare-Object $var $var2)) {
 Write-Host True
} 

---

Answer to your edit:

Your first variable ( $newContent ) is an array of strings but also includes another array of strings . See here:

PS D:\temp> $newContent -join ''
"this" "issen" "da" "first"System.Object[]"abc" "def" "12" "6""456" "def" "12" "4"

PS D:\temp> $oldContent -join ''
"this" "issen" "da" "first"a12 bc23 abca12 bc23 abg"abc" "def" "12" "6""456" "def" "12" "4"

A workaround is to pipe the variable to the Out-String cmdlet, but you might find a cleaner way to solve it ;-)

Compare-Object ($oldContent | out-string) ($newContent | out-string)