Add Content if Not Exist

stevesmothers2 · 2018-06-14T14:02:47.000Z

Hi- I’m trying to get a script to work that will add multiple lines to a text file if they don’t already exist. I’ve got the script working to add the content, but for some reason it keeps adding the content even if it’s there already. Can you please assist me? The script is as follows:

NOTE:This is only part of the script. The first part checks to see if the file is present and, if not, creates it.

Get-ChildItem “C:\users$($env:USERNAME)\appdata\LocalLow\Sun\Java\Deployment\security\exception.sites” |
Where{!(Select-String -SimpleMatch " https://site1.comrnhttps://site2.comrnhttps://site3.com " -Path $.fullname -Quiet)} |
ForEach{
$Path = $.FullName
" https://site1.comrnhttps://site2.comrnhttps://site3.com " https://lmdev.4j.lane.edu%60r%60nhttps://lmprod.4j.lane.edu%60r%60nhttps://lmrkda.c21u.velocitycloud.net%60r%60nhttps://lmrkpa.c21u.velocitycloud.net%22,(Get-Content $Path)|Set-Content $Path
}

Thanx

OregonSteve

“Never never doubt what nobody is sure about.” -Willy Wonka

Neally · 2018-06-14T14:38:36.000Z

If you post code, please use the ‘Insert Code’ button. Please and thank you!

PLEASE READ BEFORE POSTING! Read if you're new to the PowerShell forum! Programming & Development

Hi, and welcome to the PowerShell forum! Don’t apologize for being a “noob” or “newbie” or “n00b.” There’s just no need – nobody will think you’re stupid, and the forums are all about asking questions. Just ask! Use a descriptive subject. Don’t say “Need help” or “PowerShell Help”, actually summarize what the problem is. It helps the rest of us keep track of which problem is which. Don’t post massive scripts. We’re all volunteers and we don’t have time to read all that, nor will we copy…

Neally · 2018-06-14T14:41:10.000Z

basically like so?

$content = get-content $filepath
if(-not($content | select-string -pattern "$matchsomething"){
    # code to append lines
}

stevesmothers2 · 2018-06-14T15:30:35.000Z

Hi- I appreciate the brevity and your input but I am unclear on how to add this to my script (or my script to this) since I have the code to append the file as listed above. I tried using Add-Content but, as before, it keeps adding to my file regardless. My skills are beginner level so I don’t understand all the pieces. Could you expand or detail your answer a bit more?

Thanx

OregonSteve

“Never never doubt what nobody is sure about.” -Willy Wonka

Neally · 2018-06-14T15:50:09.000Z

What exactly is the string you try to match?

https://site1.com
https://site2.com
https://site3.com

is it in the file like so?

dannease · 2018-06-14T15:52:30.000Z

Perhaps like so?

$filePath = "C:\users\$($env:USERNAME)\appdata\LocalLow\Sun\Java\Deployment\security\exception.sites"
$actualContent = Get-Content $filePath
$desiredContent = @("https://site1.net","https://site2.com","https://site3.org")
foreach($item in $desiredContent){
    if($item -notin $actualContent) {$item | add-content $filePath }
}

Which basically boils down to, “For every piece of desired content, if it’s not already in the actual content, add it”. There are probably ways to shorten this for brevity, but it gets the job done.

stevesmothers2 · 2018-06-14T15:56:16.000Z

Yes, the string I’m trying to match is listed like that in the text file…

stevesmothers2 · 2018-06-14T16:00:54.000Z

Thanx, GM- These are the errors generated when I run this script in Powershell ISE:

You must provide a value expression on the right-hand side of the ‘-’ operator.
At line:5 char:14

Unexpected token ‘notin’ in expression or statement.
At line:5 char:15

Unexpected token ‘actualContent’ in expression or statement.
At line:5 char:21

Neally · 2018-06-14T16:02:40.000Z

Can you give us a sanitized sample what the text file looks like and what you are trying to match? I think that might help.

stevesmothers2 · 2018-06-14T16:25:01.000Z

It’s just as you illustrated in your sample:

Site1.net

Site2.com

Site3.org

If the user has not added an entry manually in the Java applet (which is the case for 90% of them), the file does not exist, so that’s the first part of my script is to check for the file and create it if it’s not there. Then I just need to add four URLs, each on a separate line. That’s the only content of the file…

Neally · 2018-06-14T16:44:29.000Z

HOw about like so?

$content = get-content "$env:userprofile\desktop\test.txt"
$sites   = "Site1.net","Site2.com","Site3.org"

foreach($site in $sites){
    if(-not($content -contains $site)){
        $site | out-file "$env:userprofile\desktop\test.txt" -Append -encoding utf8
    }
}

stevesmothers2 · 2018-06-14T18:04:50.000Z

I sure appreciate your assistance! I was able to mash up my script and yours to get my desired result. It might not be pretty but it gets the job done. I’ll work to get it cleaned up later… For now, it will create the file on the first run. The next run will add the content… The next run does NOTHING, just as required:

$content = get-content "C:\users\$($env:USERNAME)\path\to\file\test.txt"
$sites   = "https://site1.com","https://site2.com","https://site3.com","https://etc.com"

if (!(Test-Path "C:\users\$($env:USERNAME)\path\to\file\test.txt"))
{
   New-Item -path "C:\users\$($env:USERNAME)\path\to\file\" -name test.txt -type "file" 
}
else
{
foreach($site in $sites){
    if(-not($content -contains $site)){
        $site | out-file "C:\users\$($env:USERNAME)\path\to\file\test.txt" -Append -encoding utf8
    }
}
}

Best

OregonSteve

“Never never doubt what nobody is sure about.” -Willy Wonka

dannease · 2018-06-14T18:43:30.000Z

OregonSteve:

Thanx, GM- These are the errors generated when I run this script in Powershell ISE:

You must provide a value expression on the right-hand side of the ‘-’ operator.
At line:5 char:14

Unexpected token ‘notin’ in expression or statement.
At line:5 char:15

Unexpected token ‘actualContent’ in expression or statement.
At line:5 char:21

The -notin and -in comparison operators were introduced in PowerShell 3.0, so you must be using an older version. The re-write Neally did using -contains should work though (thanks Neally!)

@alexw