How to get Windows DNS suffix search list using c++

Question

How to get windows dns suffix serach list from ip configuration using c++ ? (.NET <= 3.5)

Answer 1

You can get them from the registry.

If set from the network control panel:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\services\Tcpip\Parameters\SearchList

If set by Group Policy:

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\SearchList

Use the Registry class to read , the same class can be use set but, you will need admin permissions to do so.

C# using Management and WMI Classes:

ManagementObjectSearcher q= new ManagementObjectSearcher("SELECT ServiceName,DNSDomainSuffixSearchOrder FROM Win32_NetworkAdapterConfiguration");// WHERE DNSDomainSuffixSearchOrder IS NOT NULL");
var qc= q.Get();

foreach (ManagementObject mo in qc)
{
    if ( mo.Properties["DNSDomainSuffixSearchOrder"] != null)
    {
        var s = mo.Properties["DNSDomainSuffixSearchOrder"];
        if (s.Value != null)
        {
            Console.WriteLine(mo["ServiceName"]);
            string[] sfxNames = s.Value as string[];
            foreach (string sx in sfxNames)
            {
                Console.WriteLine(sx);
            }
        }
    }
}