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Use -notlike to filter out multiple strings in PowerShell

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V2 at least contains the -username parameter that takes a string[], and supports globbing.

V1 you want to expand your test like so:

Get-EventLog Security | ?{$_.UserName -notlike "user1" -and $_.UserName -notlike "*user2"}

Or you could use "-notcontains" on the inline array but this would only work if you can do exact matching on the usernames.

... | ?{@("user1","user2") -notcontains $_.username}


I think Peter has the right idea. I would use a regular expression for this along with the -notmatch operator.

Get-EventLog Security | ?{$_.Username -notmatch '^user1$|^.*user$'}

In order to support "matches any of ..." scenarios, I created a function that is pretty easy to read. My version has a lot more to it because its a PowerShell 2.0 cmdlet but the version I'm pasting below should work in 1.0 and has no frills.

You call it like so:

Get-Process | Where-Match Company -Like '*VMWare*','*Microsoft*'
Get-Process | Where-Match Company -Regex '^Microsoft.*'

filter Where-Match($Selector,[String[]]$Like,[String[]]$Regex) {

    if ($Selector -is [String]) { $Value = $_.$Selector }
    elseif ($Selector -is [ScriptBlock]) { $Value = &$Selector }
    else { throw 'Selector must be a ScriptBlock or property name' }

    if ($Like.Length) {
        foreach ($Pattern in $Like) {
            if ($Value -like $Pattern) { return $_ }
        }
    }

    if ($Regex.Length) {
        foreach ($Pattern in $Regex) {
            if ($Value -match $Pattern) { return $_ }
        }
    }

}

filter Where-NotMatch($Selector,[String[]]$Like,[String[]]$Regex) {

    if ($Selector -is [String]) { $Value = $_.$Selector }
    elseif ($Selector -is [ScriptBlock]) { $Value = &$Selector }
    else { throw 'Selector must be a ScriptBlock or property name' }

    if ($Like.Length) {
        foreach ($Pattern in $Like) {
            if ($Value -like $Pattern) { return }
        }
    }

    if ($Regex.Length) {
        foreach ($Pattern in $Regex) {
            if ($Value -match $Pattern) { return }
        }
    }

    return $_

}

don't use -notLike, -notMatch with Regular-Expression works in one line:

Get-MailBoxPermission -id newsletter | ? {$_.User -NotMatch "NT-AUTORIT.*|.*-Admins|.*Administrators|.*Manage.*"}

Easiest way I find for multiple searches is to pipe them all (probably heavier CPU use) but for your example user:

Get-EventLog -LogName Security | where {$_.UserName -notlike "*user1"} |  where {$_.UserName -notlike "*user2"}