Adding an application firewall rule to both private and public networks via win7 FirewallAPI

Question

A little background: Basicaly I\'d like to add a program firewall access rule to both private and public networks.

I used to use this- \"netsh firewall add allowedpr

Answer 1

My answer is from David's answer but more detail. And fix problem about setting Localports. You need to setting Protocol before setting Localports. More detail is bellow:

the first, you need to import reference FirewallAPI.dll. It's in "C:\Windows\System32\FirewallAPI.dll" then:

using NetFwTypeLib;

and insert code into your:

        Type tNetFwPolicy2 = Type.GetTypeFromProgID("HNetCfg.FwPolicy2");
        INetFwPolicy2 fwPolicy2 = (INetFwPolicy2)Activator.CreateInstance(tNetFwPolicy2);
        var currentProfiles = fwPolicy2.CurrentProfileTypes;

        // Let's create a new rule
        INetFwRule2 inboundRule = (INetFwRule2)Activator.CreateInstance(Type.GetTypeFromProgID("HNetCfg.FWRule"));
        inboundRule.Enabled = true;
        //Allow through firewall
        inboundRule.Action = NET_FW_ACTION_.NET_FW_ACTION_ALLOW;
        //Using protocol TCP
        inboundRule.Protocol = 6; // TCP
        //Port 81
        inboundRule.LocalPorts = "81";
        //Name of rule
        inboundRule.Name = "MyRule";
        // ...//
        inboundRule.Profiles = currentProfiles;

        // Now add the rule
        INetFwPolicy2 firewallPolicy = (INetFwPolicy2)Activator.CreateInstance(Type.GetTypeFromProgID("HNetCfg.FwPolicy2"));
        firewallPolicy.Rules.Add(inboundRule);