functions/Remove-FirewallRules.ps1

<#
.SYNOPSIS
Removes firewall rules according to a list in a CSV or JSON file.
.DESCRIPTION
Removes firewall rules according to a with Export-FirewallRules generated list in a CSV or JSON file.
CSV files have to be separated with semicolons. Only the field Name or - if Name is missing - DisplayName
is used, alle other fields can be omitted
anderen
.PARAMETER CSVFile
Input file
.PARAMETER JSON
Input in JSON instead of CSV format
.NOTES
Author: Markus Scholtes
Version: 1.01
Build date: 2018/03/27
.EXAMPLE
Remove-FirewallRules
Removes all firewall rules according to a list in the CSV file FirewallRules.csv in the current directory.
.EXAMPLE
Remove-FirewallRules WmiRules.json -json
Removes all firewall rules according to the list in the JSON file WmiRules.json.
#>

function Remove-FirewallRules
{
    Param($CSVFile = ".\FirewallRules.csv", [SWITCH]$JSON)

    #Requires -Version 4.0


    if (!$JSON)
    { # read CSV file
        $FirewallRules = Get-Content $CSVFile | ConvertFrom-CSV -Delimiter ";"
    }
    else
    { # read JSON file
        $FirewallRules = Get-Content $CSVFile | ConvertFrom-JSON
    }

    # iterate rules
    ForEach ($Rule In $FirewallRules)
    {
        $CurrentRule = $NULL
        if (![STRING]::IsNullOrEmpty($Rule.Name))
        {
            $CurrentRule = Get-NetFirewallRule -EA SilentlyContinue -Name $Rule.Name
            if (!$CurrentRule)
            {
                Write-Error "Firewall rule `"$($Rule.Name)`" does not exist"
                continue
            }
        }
        else
        {
            if (![STRING]::IsNullOrEmpty($Rule.DisplayName))
            {
                $CurrentRule = Get-NetFirewallRule -EA SilentlyContinue -DisplayName $Rule.DisplayName
                if (!$CurrentRule)
                {
                    Write-Error "Firewall rule `"$($Rule.DisplayName)`" does not exist"
                    continue
                }
            }
            else
            {
                Write-Error "Failure in data record"
                continue
            }
        }

        Write-Output "Removing firewall rule `"$($CurrentRule.DisplayName)`" ($($CurrentRule.Name))"
        Get-NetFirewallRule -EA SilentlyContinue -Name $CurrentRule.Name | Remove-NetFirewallRule
    }
}