var
  reg:tregistry;
begin
  reg:=tregistry.Create;
  with reg do
    begin
      RootKey:=HKEY_LOCAL_MACHINE;
      if OpenKey('SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo',true) then
        begin
          WriteString('DSQUERY','DBNETLIB');
          WriteString('主机名','DBMSSOCN,Ip地址,端口号');
        end
      else
        begin
          OpenKey('SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo',true);
          WriteString('DSQUERY','DBNETLIB');
          WriteString('主机名','DBMSSOCN,Ip地址,端口号');
        end;
    end;
end;
把以上代码放在oncreat事件上!主机名,ip地址,端口号自己设!!!!