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Internet
HTML
JavaScript
» Programming
Windows

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Delphi
Functions
Networking
Windows 95/98/ME
Windows NT/2000/XP
Windows

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registry setdns sample

Dynamically changing TCP/IP DNS addresses

See Also

If you connect to the Internet, a Domain Name Server (DNS) is generally required to convert English Internet addresses to their natural numeric IP addresses -- to convert www.chami.com to 1.2.3.4 for example.

If you have a need to dynamically change your DNS servers from your program, you can do so by calling the the following "SetTCPIPDNSAddresses()" function with a list of DNS IP addresses separated by a single space.

uses Registry;

procedure
  SaveStringToRegistry_LOCAL_MACHINE(
  sKey, sItem, sVal : string );
var
  reg : TRegIniFile;
begin
  reg := TRegIniFile.Create( '' );
  reg.RootKey := HKEY_LOCAL_MACHINE;
  reg.WriteString(
    sKey, sItem, sVal + #0 );
  reg.Free;
end;

Listing #1 : Delphi code. Download registry (0.3 KB).

procedure
  SetTCPIPDNSAddresses(
  sIPs : string );
begin
  //
  // if using Windows NT
  //
  SaveStringToRegistry_LOCAL_MACHINE(
    'SYSTEMCurrentControlSet' +
    'ServicesTcpipParameters',
    'NameServer',
    sIPs );

  //
  // if using Windows 95
  //
  SaveStringToRegistry_LOCAL_MACHINE(
    'SYSTEMCurrentControlSet' +
    'ServicesVxDMSTCP',
    'NameServer',
    sIPs );
end;

Listing #2 : Delphi code. Download setdns (0.33 KB).

For example, if you want to set two DNS server addresses -- 1.2.3.4 and 5.6.7.8 here's how your function call would look like:

SetTCPIPDNSAddresses(
'1.2.3.4 5.6.7.8' );

Listing #3 : Delphi code. Download sample (0.17 KB).

Applicable Keywords : Delphi, Delphi 2.x, Delphi 3.x, Functions, Networking, Windows NT, Windows NT 3.x, Windows NT 4.x, Windows, Win32, Windows 95

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