GetRandomString.psm1
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function Get-Random-String { <# .SYNOPSIS Generates a random string with an array of customisations .DESCRIPTION This cmdlet generates a random string based on user customisation. .EXAMPLE rndmstr 32 ukmshszqvkwhivrevecpsrnqnvpjuvpkt .EXAMPLE rndmstr 32 -UseUpperCase LSlBajOMOAsyCeHipDWOiblIbiOrGSkfu .EXAMPLE rndmstr 32 -UseUpperCase -UseNumbers FYyU7bIUoFKJr3975ZAJc8jeCnVhjlZqT .EXAMPLE rndmstr 32 -UseUpperCase -UseLoweCase:$false ARKDMQJFILYWYTAZNSRQOUFYLFTMIZEWV .EXAMPLE rndmstr 32 -UseUpperCase -UseNumbers -UseSpecialCharacters bFNC1D1K*ng37neaYYpT0J985+ZCaC47h #> [CmdletBinding()] [Alias('rndmstr')] param( [Parameter( Mandatory=$true, HelpMessage="The character length of the requested random string" )] [int] $StringLength, [Parameter(HelpMessage="Adds Lower-Case latin characters to the string pool")] [switch] $UseLowerCase = $true, [Parameter(HelpMessage="Adds Upper-Case latin characters to the string pool")] [switch] $UseUpperCase = $false, [Parameter(HelpMessage="Adds numeric characters to the string pool")] [switch] $UseNumbers = $false, [Parameter(HelpMessage="Adds the special characters: '!@#$%^&*_+-' to the string pool")] [switch] $UseSpecialCharacters = $false, [Parameter(HelpMessage="Characters here will be added to the string pool")] [string] $IncludeCharacters = "", [Parameter(HelpMessage="Characters here will be removed to the string pool")] [string] $ExcludeCharacters = "" ) if( !($UseLowerCase) -and !($UseUpperCase) -and !($UseNumbers) -and !($UseSpecialCharacters) -and ($IncludeCharacters -eq "") ){ throw "No Characters allowed. Please use some of the parameter flags to enable character sets." } # Initate character sets $Letters = "ABCDEFGHIJKLMNOPQRSTUVWYZ" $Numbers = "0123456789" $SpecialCharacters = "!@#$%^&*_+-" # Populate the pool so that each character has a chance to be picked $Pool = "" for ($i = 0 ; $i -lt $StringLength ; $i++){ if($UseUpperCase) {$Pool+=$Letters} if($UseLowerCase) {$Pool+=$Letters.ToLower()} if($UseNumbers){$Pool+=$Numbers } if($UseSpecialCharacters){$Pool+=$SpecialCharacters} $Pool+=$IncludeCharacters } # Remove Excluded characters foreach ($Char in $ExcludeCharacters.toCharArray()) { $Pool = $Pool -replace '['+$Char+']','' } if($Pool -eq ""){ throw "No Characters allowed. All available characters were excluded by user." } # Sort by Get-Random to shuffle (Get-Random is a secure random) $Shuffle = $($Pool.tochararray() | Sort-Object {Get-Random}) # Return the first N charachters as a string return $Shuffle[0..$StringLength] -join '' } |