======Microsoft - Scripting - PowerShell - Notes======
=====Determine PowerShell version=====
<code powershell>
$PSVersionTable.PSVersion
</code>
[[http://stackoverflow.com/questions/1825585/determine-installed-powershell-version|Stack Overflow - Determine installed PowerShell version]] \\
=====Arrays=====
[[http://thephuck.com/scripts/easy-way-to-check-if-your-powershell-variable-is-an-array-or-not/|ThepHuck - Easy way to check if your PowerShell variable is an array or not]] \\

====Array has fixed size====
Using the .Add or .RemoveRange methods on an array object in PowerShell will not work.

The Array.IsFixedSize property is always true for all arrays.

Source: [[https://msdn.microsoft.com/en-us/library/system.array.isfixedsize.aspx|Microsoft MSDN - Array.IsFixedSize Property]] via [[https://social.msdn.microsoft.com/Forums/en-US/c13ea9bd-dac4-44be-99f7-272a8eb0c55d/using-the-add-method-on-an-array?forum=winserverpowershell|Microsoft MSDN forum - Using the .Add method on an array]] \\

=====Printer=====
Get the Name, port, location, comment, drivername and printservername of every printer on this system and export this to a CSV:
<code powershell>
Get-WmiObject Win32_Printer | Select-Object Name,PortName,Location,Comment,DriverName,SystemName | Export-CSV test.csv
</code>

=====Bug in Powershell v3 on regional settings=====
On Windows Server 2012 RTM with a language setting other than en-US, several fields in PowerShell output are empty.

An example are the LevelDisplayName and Message fields of the Get-WinEvent cmdlet.

To work around this use the following function in your script:
<code>
function Using-Culture (
  [System.Globalization.CultureInfo]
  $culture = (throw "USAGE: Using-Culture -Culture culture -Script {...}"),
  [ScriptBlock]
  $script = (throw "USAGE: Using-Culture -Culture culture -Script {...}"))
{
    $OldCulture = [Threading.Thread]::CurrentThread.CurrentCulture
    $OldUICulture = [Threading.Thread]::CurrentThread.CurrentUICulture    
    try {        
        [Threading.Thread]::CurrentThread.CurrentCulture = $culture        
        [Threading.Thread]::CurrentThread.CurrentUICulture = $culture        
        Invoke-Command $script    
    }    
    finally {        
        [Threading.Thread]::CurrentThread.CurrentCulture = $OldCulture        
        [Threading.Thread]::CurrentThread.CurrentUICulture = $OldUICulture    
    }
}
</code>
Source: Keith Hill on [[http://stackoverflow.com/questions/4105224/how-to-set-culture-in-powershell|stackoverflow - How to set culture in PowerShell?]] \\

And execute Get-WinEvent like so:
<code>
Using-Culture -Culture en-US -Script {Get-WinEvent -logname System -maxevents 10 -computername Server01}
</code>

Sources: \\
[[http://vniklas.djungeln.se/2013/01/09/bug-in-get-winevent-on-windows-2012/|vNiklas Virtualization blog - Bug in Get-WinEvent on Windows 2012?]] \\
[[http://vniklas.djungeln.se/2013/01/09/bug-in-powershell-v3-on-regional-settings-in-windows-2012/|vNiklas Virtualization blog - Bug in Powershell v3 on regional settings in Windows 2012]] \\
[[http://stackoverflow.com/questions/10534982/powershell-get-winevent-has-no-messsage-data|stackoverflow - powershell: get-winevent has no messsage data?]] \\
[[https://connect.microsoft.com/PowerShell/feedback/details/716533/get-winevent-does-not-return-the-content-of-the-event-message-in-v3-ctp2|Microsoft Connect - Get-WinEvent does not return the content of the Event Message in V3 CTP2]] \\

=====If today is the fourth Saturday of the month=====
Quick and dirty way to check if today is the fourth Saturday of this month:
<code>
$dateCurrentDay = Get-Date
if ( $dateCurrentDay.DayOfWeek -eq "Saturday" ) {

	# If this Saturday is the fourth Saturday of the month...
	if ( ($dateCurrentDay.Day / 7 -gt 3) -and ($dateCurrentDay.Day / 7 -le 4) ) {

		"Do something."

	}
}
</code>

=====Write to text file=====
Append a line of text to a file:
<code>
$strLogFile = "C:\TEMP\script.log"
"Removing current files:" | Out-File -FilePath "$strLogFile" -Append
</code>
The same can be done with command output:
<code>
Get-Item "C:\Windows\Temp\*.tmp" | Out-File -FilePath "$strLogFile" -Append
</code>

=====Take arguments=====
To use a parameter 
<code>
$strJobName = [string]$args[0]
</code>
Source: [[http://stackoverflow.com/questions/6359618/pass-parameter-from-batch-file-to-the-powershell-script|Stackoverflow - Pass parameter from batch file to the powershell script]] \\


=====Add parameters=====

Add to the beginning of the script:
<code powershell>
[CmdletBinding()]
param(
  [Parameter(Mandatory)]
  [string]$TaskName,
  
  [Parameter()]
  [string]$Property
)
</code>

Types can be (among others):
  * string
  * switch
  * int
  * boolean

Source:
  * [[https://docs.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_parameter_sets|Microsoft Docs - about_Parameter_Sets]]
  * [[https://ss64.com/ps/syntax-args.html|SS64.com - PowerShell Parameters]]
  * [[https://ss64.com/ps/syntax-function-advanced.html|SS64.com - Write an Advanced Function]]


=====Rename computer=====
Rename the local computer and restart:
<code powershell>
Rename-Computer -NewName newcomputername -Restart
</code>

=====Restart computer=====
Restart the local computer:
<code powershell>
Restart-Computer
</code>

=====Promote first AD DS Domain Controller=====

<code powershell>
Import-Module ADDSDeployment
Install-ADDSForest `
-CreateDnsDelegation:$false `
-DatabasePath "C:\Windows\NTDS" `
-DomainMode "Win2008" `
-DomainName "testing.local" `
-DomainNetbiosName "TESTING" `
-ForestMode "Win2008" `
-InstallDns:$true `
-LogPath "C:\Windows\NTDS" `
-NoRebootOnCompletion:$false `
-SysvolPath "C:\Windows\SYSVOL" `
-Force:$true
</code>

=====Create an object and add it to another=====
<code powershell>
# Create the objReport variable
$objReport = @()

foreach ( $strSomething in $arrSomething ) {

	# Create the objTemp variable
	$objTemp = "" | Select-Object "Name","Missing Group","Group Permissions"
	
	# Fill the objTemp variable
	$objTemp."Name" = $strName
	$objTemp."Missing Group" = $strGroup
	$objTemp."Group Permissions" = $strPerms

	# Add the filled objTemp to objReport
	$objReport += $objTemp

	# Cleanup
	$objTemp = $null

}

# Display the report
$objReport

# Cleanup
$objReport = $null
</code>

=====Redirect StdError and StdOutput to the same log file=====
To redirect both standard and error output from a command line tool to a text file from PowerShell, either use:
<code>
command.exe 2>&1 | Out-File C:\Logs\Logfile.txt
</code>
Or:
<code>
command.exe 2>&1 > C:\Logs\Logfile.txt
</code>
Source:[[http://stackoverflow.com/questions/8925323/redirection-of-standard-and-error-output-appending-to-the-same-log-file|Stack Overflow - Redirection of standard and error output appending to the same log-file]] \\

=====Check if the PowerShell prompt is elevated=====

<code powershell>
# Check if the PowerShell prompt was started with elevation:
# Source: http://stackoverflow.com/questions/7985755/how-to-detect-if-cmd-is-running-as-administrator-has-elevated-privileges
$objPrincipal = new-object System.Security.Principal.WindowsPrincipal([System.Security.Principal.WindowsIdentity]::GetCurrent())
if ($objPrincipal.IsInRole([System.Security.Principal.WindowsBuiltInRole]::Administrator)) {

	Write-Host "Please start this script in an elevated PowerShell prompt." -ForeGroundColor Red
	Exit

}
</code>
Source: [[http://stackoverflow.com/questions/7985755/how-to-detect-if-cmd-is-running-as-administrator-|Stack Overflow - How to detect if CMD is running as Administrator/has elevated privileges?]] \\


=====Get UNIX time=====

<code powershell>
Get-Date -UFormat %s
</code>

Get UNIX time from 30 days ago:
<code powershell>
Get-Date -UFormat %s (Get-Date).AddDays(-30)
</code>

Source: [[https://devblogs.microsoft.com/scripting/powertip-use-unix-date-formatting-in-powershell/|Microsoft Scripting - PowerTip: Use UNIX Date Formatting in PowerShell]]


=====Hexadecimal to Decimal and Decimal to Hexadecimal======

Hex to dec:
<code>
[uint32]0x41303
</code>
Source: [[https://stackoverflow.com/questions/38567479/hex-to-decimal-conversion-powershell-5#38567654|stack overflow - Hex to Decimal Conversion - PowerShell 5]]

Dec to hex:
<code>
"0x{0:X}" -f 267011
</code>>
Source: [[https://stackoverflow.com/questions/54512136/how-to-convert-decimal-to-hexadecimal-variable#57999927|stack overflow - How to convert decimal to hexadecimal variable?]]


=====Convert UTC DateTime to another timezone=====

<code powershell>
$datetime = Get-Date
$datetime.ToUniversalTime()
[TimeZoneInfo]::ConvertTimeBySystemTimeZoneId($datetime, 'W. Europe Standard Time')
</code>

To get a list of timezones:
<code powershell>
[TimeZoneInfo]::GetSystemTimeZones() | Select-Object Id, DisplayName
</code>

Source:[[https://stackoverflow.com/questions/58802973/how-to-convert-powershell-utc-datetime-object-to-est|stack overflow - How to convert powershell UTC datetime object to EST]]


=====Print error message=====

Print most recent error message:
<code powershell>
$Error[0].Exception
</code>