Powershell search in String and extract specific values of a string

Assuming that each line's list of key-value pairs only contain values without embedded whitespace or quoting:

# Sample input line.
$line = 'ts=2019-01-16 network=1.1.1.1 system=irgendwas pid1=100 bugReq=dasf something=else maybe=this'

# Parse the line into key-value pairs and create a variable for each.
$i = 0
foreach ($keyOrValue in $line -split '[= ]') {
  if ($i++ % 2 -eq 0) { $varName = $keyOrValue }
  else                { Set-Variable $varName $keyOrValue }
}

# $ts now contains '2019-01-16', $network '1.1.1.1', $system 'irgendwas', ...

Note how I've modified your sample input line slightly to change pid to pid1, because PowerShell won't allow you to create a $PID variable, because it is an automatic variable reflecting the current session's PID (process ID).

Another option (which would also avoid the variable-name conflict) is to create a hashtable for each input line:

# Sample input line.
$line = 'ts=2019-01-16 network=1.1.1.1 system=irgendwas pid=100 bugReq=dasf something=else maybe=this'

# Parse the line into key-value pairs and create a variable for each.
$htValues = @{} # Initialize the hashtable.
$i = 0
foreach ($keyOrValue in $line -split '[= ]') {
  if ($i++ % 2 -eq 0) { $varName = $keyOrValue }
  else                { $htValues[$varName] = $keyOrValue }
}

# $htValues now has keys 'ts', 'network', 'system' with corresponding
# values, so you can access $htValues.ts to get '2019-01-16', for instance.

This approach has the added advantage of lending itself to collecting the hashtables created for the individual lines in an overall array (e.g., $hashTableArray = foreach ($line in ...) { ... } - though with a really big file that may not be an option.

Borrowing an idea from Lee_Dailey's answer, you can alternatively use the ConvertFrom-StringData cmdlet to create the hashtable, after first placing each key-value pair onto its own line with the help of the -replace operator:

$htValues = ConvertFrom-StringData ($line -replace ' ', "`n")

The caveat re ConvertFrom-StringData is that it interprets \ chars. as starting escape sequences; for instance, a value such as b\c breaks the command:

Convertfrom-StringData 'a=b\c' # ERROR: "parsing 'b\c' - Missing control character."

On the plus side, use of ConvertFrom-StringData is much faster than manual parsing with foreach.

As an aside: PowerShell's Get-Content cmdlet for reading lines one by one (by default) is convenient, but slow.

To process a (large) text file's lines one by one more quickly, use :

$file = 'file.txt'
foreach ($line in [System.IO.File]::ReadLines((Convert-Path $file))) {
  # ...
}

So how the log you are showing me works looks like there are 3 sections we can cut and paste from Object, Which can be returned from new line Keypair, Which can be returned from empty space Key, which can be returned from removing =

I wrote a function for this case using that idea

function ConvertTo-PsObjectArrayList($Text,$TextObjectSeparator,$KeyPairSeparator,$KeySeparator){
    $ArrayList = New-Object System.Collections.ArrayList
    $TestData -split $TextObjectSeparator | %{
        $PsObject = new-object System.Management.Automation.PSObject
        $_ -split $KeyPairSeparator | %{      
            $KeyPair = $_ -split $KeySeparator
            $PsObject | Add-Member -MemberType NoteProperty -Name $KeyPair[0] -Value $KeyPair[1]
        }
        $ArrayList.Add($PsObject) | out-null
    }
    return $ArrayList
}

$TestData = @'
ts=2019-01-16 network=1.1.1.1 system=irgendwas pid=100 bugReq=dasf something=else maybe=this
ts=2019-01-16 network=1.1.2.1 system=irgendwas pid=130 bugReq=dasf something=else
ts=2019-01-16 network=1.1.1.1 system=irgendwas pid=150 bugReq=dasf something=else maybe=this
ts=2019-01-16 network=1.1.1.1 system=irgendwas pid=110 bugReq=dasf something=else
'@

ConvertTo-PsObjectArrayList -Text $TestData -TextObjectSeparator "`r`n" -KeyPairSeparator " " -KeySeparator "=" | select TS, System, Something

This would return

ts         system    something
--         ------    ---------
2019-01-16 irgendwas else     
2019-01-16 irgendwas else     
2019-01-16 irgendwas else     
2019-01-16 irgendwas else