Split text by columns in PowerShell

Question

I\'m a PowerShell novice (Bash is my thing normally) who\'s currently trying to obtain qwinsta output to show who is logged in as an \'rdpwd\' (rdesktop) user so that I can

Answer 1

Honestly I'd look up a better way to do this, but you can fudge it with some text manipulation and the ConvertFrom-Csv cmdlet:

$(qwinsta.exe) -replace "^[\s>]" , "" -replace "\s+" , "," | ConvertFrom-Csv | select username

Firstly replace any leading spaces or > characters with nothing, then replace any white spaces with a comma. Then you can pipe to ConvertFrom-Csv and work with the data as an object.

EDIT

Actually, the above has some issues, mostly with the \s+ because if a column is blank it does not get correctly recognised as a blank field, and the next text is incorrectly promoted to the current field.

The below is a full blown parser for this command, and would probably work for any sort of tabulated output from a native windows exe:

$o = @()
$op = $(qwinsta.exe)

$ma = $op[0] | Select-String "(?:[\s](\w+))" -AllMatches
$ErrorActionPreference = "Stop"

for($j=1; $j -lt $op.length; $j++) {
    $i = 0
    $obj = new-object pscustomobject
    while ($i -lt $ma.matches.count) { 
      $prop = $ma.matches[$i].groups[1].value; 
      $substrStart = $ma.matches[$i].index 
      $substrLen = $ma.matches[$i+1].index - $substrStart
      try {
        $obj | Add-Member $prop -notepropertyvalue $op[$j].substring($substrStart,$substrLen).trim() 
      }
      catch [ArgumentOutOfRangeException] {
        $substrLen = $op[$j].length - $substrStart 
        if($substrLen -gt 0) {
          $obj | Add-Member $prop -notepropertyvalue $op[$j].substring($substrStart,$substrLen).trim()
        }
        else {
          $obj | Add-Member $prop -notepropertyvalue ""
        }
      }
      $i++
    }
    $o += ,$obj
}

$o | ? { $_.type -eq 'rdpwd'} | select username

USERNAME
--------
user.name1
user.name2
user.name3

Answer 2

Can't tell for sure, but it sounds like you're trying to do a regex split using the string .split() method. That doesn't work. Use the Powershell -split operator to do a regex split:

(@'
SESSIONNAME       USERNAME        ID     STATE   TYPE      DEVICE
services                          0      Disc
console                           1      Conn
rdp-tcp#0         user.name1      2      Active  rdpwd
rdp-tcp#1         user.name2      3      Active  rdpwd
rdp-tcp#1         user.name3      4      Active  rdpwd
rdp-tcp                           65536  Liste
'@).split("`n") |
foreach {$_.trim()} | sv x


$x -match 'rdpwd' |
foreach { ($_ -split '\s+')[1] }

user.name1
user.name2
user.name3

Answer 3

a simple way

get list of active users only

$logonusers = qwinsta /server:ts33 | Out-String -Stream | Select-String "Active"

clears all the info up apart from the users, with -replace command

$logonusers = $logonusers -replace("rdp-tcp") -replace("Active") -
replace("rdpwd") -replace("#") -replace '\s+', ' ' -replace '[0-9]',' '

$logonusers

will then list all the active users.

Answer 4

I wrote a reusable ConvertFrom-SourceTable cmdlet which is available for download at the PowerShell Gallery and the source code from the GitHub iRon7/ConvertFrom-SourceTable repository.

$Object = ConvertFrom-SourceTable '
SESSIONNAME       USERNAME        ID     STATE   TYPE      DEVICE
services                          0      Disc
console                           1      Conn
rdp-tcp#0         user.name1      2      Active  rdpwd
rdp-tcp#1         user.name2      3      Active  rdpwd
rdp-tcp#1         user.name3      4      Active  rdpwd
rdp-tcp                           65536  Listen
'

It pretty flexible and capable of reading a lot of table format including reading the output of the results. Or even if e.g. the ID column is right aligned meaning that it would concern integers rather than strings:

$Object = ConvertFrom-SourceTable '
   ID TYPE  USERNAME   STATE  DEVICE SESSIONNAME
   -- ----  --------   -----  ------ -----------
    0                  Disc          services
    1                  Conn          console
    2 rdpwd user.name1 Active        rdp-tcp#0
    3 rdpwd user.name2 Active        rdp-tcp#1
    4 rdpwd user.name3 Active        rdp-tcp#1
65536                  Listen        rdp-tcp
'

For details see: ConvertFrom-SourceTable -?

Answer 5

Print field 4,5 and 6 in second column.

awk 'NR>3&&NR<7{print $2}' file

    user.name1
    user.name2
    user.name3

Answer 6

I like Matt's answer for this, however it has issues with spaces in column headings (they are problematic in general, but sometimes you can't do much). Here's a tweaked, functionized version to help. Note you could probably tweak the preproc to include e.g. tabs or other delimiters but still relies on per-line indexes being constant.

function Convert-TextColumnsToObject([String]$data)
{
    $splitLinesOn=[Environment]::NewLine
    $columnPreproc="\s{2,}"
    $headerString = $data.Split($splitLinesOn) | select -f 1
    #Preprocess to handle headings with spaces
    $headerElements = ($headerString -replace "$columnPreproc", "|") -split "\|" | Where-Object{$_}
    $headerIndexes = $headerElements | ForEach-Object{$headerString.IndexOf($_)}
    $results = $data.Split($splitLinesOn) | Select-Object -Skip 1  | ForEach-Object{
        $props = @{}
        $line = $_
        For($indexStep = 0; $indexStep -le $headerIndexes.Count - 1; $indexStep++){
            $value = $null            # Assume a null value 
            $valueLength = $headerIndexes[$indexStep + 1] - $headerIndexes[$indexStep]
            $valueStart = $headerIndexes[$indexStep]
            If(($valueLength -gt 0) -and (($valueStart + $valueLength) -lt $line.Length)){
                $value = ($line.Substring($valueStart,$valueLength)).Trim()
            } ElseIf ($valueStart -lt $line.Length){
                $value = ($line.Substring($valueStart)).Trim()
            }
            $props.($headerElements[$indexStep]) = $value    
        }
        [pscustomobject]$props
    }

    return $results
} 

Example:

$data= @"
    DRIVER              VOLUME NAME
    local               004e9c5f2ecf96345297965d3f98e24f7a6a69f5c848096e81f3d5ba4cb60f1e
    local               081211bd5d09c23f8ed60fe63386291a0cf452261b8be86fc154b431280c0c11
    local               112be82400a10456da2e721a07389f21b4e88744f64d9a1bd8ff2379f54a0d28
    "@ 

$obj=Convert-TextColumnsToObject $data
$obj | ?{ $_."VOLUME NAME" -match "112be" }