How do I convert from HEX to dec having select-string outputs

Question

I'm stuck at a powershell problem - I need to get current active power scheme, precisely Turn off display after ... setting.

I have the HEX settings from powercfg select-object, but I can't seem to figure out how to separate the current AC /DC plans and convert the HEXes. I know I need to convert a HEX to DEC with [int32] but how do I access the HEX?

powercfg /QUERY | Select-String -Pattern "Turn off display after" -Context 2, 7

with an output of:

Subgroup GUID: 7516b95f-f776-4464-8c53-06167f40cc99  (Display)
      GUID Alias: SUB_VIDEO
>     Power Setting GUID: 3c0bc021-c8a8-4e07-a973-6b14cbcb2b7e  (Turn off display after)
        GUID Alias: VIDEOIDLE
        Minimum Possible Setting: 0x00000000
        Maximum Possible Setting: 0xffffffff
        Possible Settings increment: 0x00000001
        Possible Settings units: Seconds
      Current AC Power Setting Index: 0x00000000
      Current DC Power Setting Index: 0x00000000

Answer 1

Preface:

• For a more robust, culture-independent way to query power settings, see this answer.

• With the Get-PowerCfg convenience function from that answer defined, (Get-PowerCfg).monitor_timeout.AC and (Get-PowerCfg).monitor_timeout.DC would robustly yield the desired results, expressed in minutes.

---

The following assumes that you want to extract the hex numbers embedded in the last two lines of your output:

[int] $ac, [int] $dc =
   (
     powercfg /QUERY |
     Select-String -Pattern 'Turn off display after' -Context 2, 7 |
     ForEach-Object { $_.Context.PostContext[-2, -1] }
   ) -replace '^.+: '

• $_.Context.PostContext is needed to access the post context, i.e. the lines after a matching one, and [-2, -1] extracts the last two lines from it.

• -replace '^.+: ' removes everything before the hex number from the resulting lines.

• Type-constraining the target variables with [int] automatically converts the hex-number strings to integers.

  • Note: Using [int], i.e. [System.Int32] causes hex values with the hight bit set to become negative numbers; e.g. 0xFFFFFFFF becomes -1; use [UInt32] instead to avoid that.

Answer 2

Try following :

$powercfg = @"
Subgroup GUID: 7516b95f-f776-4464-8c53-06167f40cc99  (Display)
      GUID Alias: SUB_VIDEO
      Power Setting GUID: 3c0bc021-c8a8-4e07-a973-6b14cbcb2b7e  (Turn off display after)
        GUID Alias: VIDEOIDLE
        Minimum Possible Setting: 0x00000000
        Maximum Possible Setting: 0xffffffff
        Possible Settings increment: 0x00000001
        Possible Settings units: Seconds
      Current AC Power Setting Index: 0x00000000
      Current DC Power Setting Index: 0x00000000
"@
$results = $powercfg | Select-String -Pattern "Turn off display after" -Context 2,8
$reader = [System.IO.StringReader]::new($results)
$table = [System.Collections.ArrayList]@()
While(($line = $reader.ReadLine()) -ne $null)
{
   $line -Match '>?(?<key>[^:]+):(?<value>.*)' | Out-Null
   $key = $Matches['key'].Trim() 
   $value = $Matches['value'].Trim()
   if($value -Match '0x[0-9a-fA-F]+')
   {
      $value = [int]::Parse($Matches[0].SubString(2), [System.Globalization.NumberStyles]::HexNumber)
   }
   $newRow = New-Object -TypeName psobject
   $newRow | Add-Member -NotePropertyName Name -NotePropertyValue $key
   $newRow | Add-Member -NotePropertyName Value -NotePropertyValue $value
   $table.Add($newRow)  | Out-Null
}
$table