Private/Get-SubnetMask.ps1
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<# .SYNOPSIS Converts a given Cidr to its subnet mask .PARAMETER Cidr The download page to look for the download link. .EXAMPLE Get-SubnetMask -Cidr 24 #> Function Get-SubnetMask { Param( [Parameter(Mandatory)] [ValidateRange(0, 32)] [int]$Cidr ) # Create a 32-character string of '1's for the network portion and '0's for the host portion $binaryString = ('1' * $Cidr).PadRight(32, '0') # Split the binary string into four 8-bit octets $octet1 = $binaryString.Substring(0, 8) $octet2 = $binaryString.Substring(8, 8) $octet3 = $binaryString.Substring(16, 8) $octet4 = $binaryString.Substring(24, 8) # Convert each binary octet to a decimal number $decimalOctet1 = [convert]::ToInt32($octet1, 2) $decimalOctet2 = [convert]::ToInt32($octet2, 2) $decimalOctet3 = [convert]::ToInt32($octet3, 2) $decimalOctet4 = [convert]::ToInt32($octet4, 2) # Format and return the subnet mask string return "$decimalOctet1.$decimalOctet2.$decimalOctet3.$decimalOctet4" } |