Solved

Obtaining DNS Primary and Secondary Address

Posted on 2002-03-30
3
786 Views
Last Modified: 2007-11-27
I need to know how to obtain both the primary and secondary DNS addresses from a machine currently connected to the net.

Assume that I will already know if a connection is present, I just need to obtain the DNS numbers and assign them to a String variable in the proper Quad format.
0
Comment
Question by:quantum2
3 Comments
 
LVL 14

Expert Comment

by:DragonSlayer
ID: 6909712
I don't know if this is the proper format, but if you just need to obtain it from the registry, here goes: (Win2K)

Navigate to HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Tcpip\Parameters\Adapters

Loop through the name of the keys to obtain the network interfaces you have (they are enclosed in braces, {}, eg {E0149FCC-34D2-4158-884B-A06F3B6F0F8E})

Let's say you managed to get {E0149FCC-34D2-4158-884B-A06F3B6F0F8E} (that is, HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Tcpip\Parameters\Adapters{E0149FCC-34D2-4158-884B-A06F3B6F0F8E}), remember the key, then navigate to HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Tcpip\Parameters\Interfaces\YourKeyName, eg. HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Tcpip\Parameters\Interfaces\{E0149FCC-34D2-4158-884B-A06F3B6F0F8E}

Open the key, then read the value for NameServer. The DNS servers are separated by a comma.


HTH
DragonSlayer
0
 
LVL 11

Accepted Solution

by:
shaneholmes earned 100 total points
ID: 6911405
Try this function "GetDNSIP"


 function GetDnsIp : string;
 var
   Output        : TStringList;
   DnsIp,
   CmdLine       : string;
 begin
   CmdLine := GetIpCfgExePath;
   if CmdLine <> '' then
   begin
     Output := TStringList.Create;
     try
       case GetBasicOsType of
         VER_PLATFORM_WIN32_WINDOWS :
         begin
           if ExecAndGetConsoleOutput (CmdLine, Output) then
             Output.LoadFromFile (GetIpCfg9xOutPath);
         end;
         else
           ExecAndGetConsoleOutput (CmdLine, Output);
       end;
       if GetDnsIpFromIpCfgOut (Output, DnsIp) then
         Result := DnsIp
       else
       begin
         //
         // Attempt to locate via registry
         //
         Result := GetDnsIpFromReg;
       end;
     finally
       Output.Free;
     end;
   end;
 end;

 

function GetDnsIpFromReg : string;
 var
   OpenKey       : HKEY;
   Vn,
   SubKey        : PChar;
   DataType,
   DataSize      : integer;
   Temp          : array [0..2048] of char;
 begin
   Result := '';
   SubKey := '';
   Vn := '';
   case GetBasicOsType of
     VER_PLATFORM_WIN32_WINDOWS  :
     begin
       SubKey := REG_9X_NAMESERVER_PATH;
      Vn := REG_9X_NAMESERVER;
     end;
     VER_PLATFORM_WIN32_NT       :
     begin
       SubKey := REG_NT_NAMESERVER_PATH;
       Vn := REG_NT_NAMESERVER;
     end;
   end;
   if RegOpenKeyEx (HKEY_LOCAL_MACHINE, SubKey, REG_OPTION_NON_VOLATILE,
     KEY_READ, OpenKey) = ERROR_SUCCESS then
   begin
     DataType := REG_SZ;
     DataSize := SizeOf(Temp);
     if RegQueryValueEx (OpenKey, Vn, nil, @DataType, @Temp,
       @DataSize) = ERROR_SUCCESS then
       Result := string(Temp);
     RegCloseKey (OpenKey);
   end;
 end;

function GetDnsIpFromIpCfgOut (const Output : TStringList;
   var DnsIp : string) : boolean;
 var
   i     : integer;
 begin
   Result := FALSE;
   if Output.Count >= 1 then
     for i := 0 to Output.Count - 1 do
     begin
       if Pos(IPCFG_DNS_SERVER_LINE, Output[i]) > 0 then
       begin
         DnsIp := Trim(Copy (Output[i], Pos(':', Output[i])+1,
           Length(Output[i])));
         Result := LooksLikeIp (DnsIp);
       end;
     end;
 end;
0
 
LVL 1

Author Comment

by:quantum2
ID: 6942364
Thanks a bunch...
Just what I was looking for. I really apprecaite the help.

Quantum2
0

Featured Post

Is Your Active Directory as Secure as You Think?

More than 75% of all records are compromised because of the loss or theft of a privileged credential. Experts have been exploring Active Directory infrastructure to identify key threats and establish best practices for keeping data safe. Attend this month’s webinar to learn more.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Intraweb submit form as a POST request 4 263
select query - oracle 16 92
Performance of SQL statement 37 97
Moving (cutting/pasting) controls in a TTabbedNotebook... 7 27
Hello everybody This Article will show you how to validate number with TEdit control, What's the TEdit control? TEdit is a standard Windows edit control on a form, it allows to user to write, read and copy/paste single line of text. Usua…
Introduction Raise your hands if you were as upset with FireMonkey as I was when I discovered that there was no TListview.  I use TListView in almost all of my applications I've written, and I was not going to compromise by resorting to TStringGrid…
This Micro Tutorial will give you a basic overview how to record your screen with Microsoft Expression Encoder. This program is still free and open for the public to download. This will be demonstrated using Microsoft Expression Encoder 4.
Many functions in Excel can make decisions. The most simple of these is the IF function: it returns a value depending on whether a condition you describe is true or false. Once you get the hang of using the IF function, you will find it easier to us…

911 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

24 Experts available now in Live!

Get 1:1 Help Now