Mega Code Archive
How to get a ip address of a domain name
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{ You must be connected to the internet and don't forget to add this
unit to get it to work :-) }
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs,winsock, StdCtrls;
type
TForm1 = class(TForm)
Button1: TButton;
Edit1: TEdit;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
function ConvertDomainIP( sHost:string): Boolean;
{ Public declarations }
end;
type
TName = array[0..100] of Char;
PName = ^TName;
var
Form1: TForm1;
sErrorWAS:string;
implementation
{$R *.dfm}
function Tform1.ConvertDomainIP( sHost:string): Boolean;
var
HEnt: pHostEnt;
HName: PName;
WSAData: TWSAData;
sIPAddr, sWSAError: string;
iCnt,i: Integer;
begin
Result := False;
if WSAStartup($0101, WSAData) <> 0 then begin
sWSAError := 'WSAStartup error';
Exit;
end;
sIPAddr := '';
sWSAError := '';
New(HName);
for i:=0 to length(sHost) do
HName^[i]:=shost[i+1];
HEnt := GetHostByName(HName^);
if HEnt <> nil then begin
Result := True;
for iCnt := 0 to HEnt^.h_length - 1 do
sIPAddr := sIPAddr + IntToStr(Ord(HEnt^.h_addr_list^[iCnt])) + '.';
SetLength(sIPAddr, Length(sIPAddr) - 1);
edit1.Text :=sIPAddr; //displays the IP address of the domain name
end
else begin
result :=false;
case WSAGetLastError of // possible errors to display
WSANOTINITIALISED:
sWSAError := 'A successful WSAStartup must occur before using this function.';
WSAENETDOWN:
sWSAError := 'The network subsystem has failed.';
WSAHOST_NOT_FOUND:
sWSAError := 'Authoritative Answer Host not found.';
WSATRY_AGAIN:
sWSAError := 'Non-Authoritative Host not found, or server failed.';
WSANO_RECOVERY:
sWSAError := 'Nonrecoverable error occurred.';
WSANO_DATA:
sWSAError := 'Valid name, no data record of requested type.';
WSAEINPROGRESS:
sWSAError := 'A blocking Windows Sockets 1.1 call is in progress, or the ' +
'service provider is still processing a callback function.';
WSAEAFNOSUPPORT:
sWSAError := 'The type specified is not supported by the Windows '+
'Sockets implementation.';
WSAEFAULT:
sWSAError := 'The addr parameter is not a valid part of the user address '+
'space, or the len parameter is too small.';
WSAEINTR:
sWSAError := 'A blocking Windows Socket 1.1 call was canceled through '+
'WSACancelBlockingCall.';
else
sWSAError := 'UNKNOWN';
end;
sErrorWAS :=sWSAError;
end;
Dispose(HName);
WSACleanup;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
if ConvertDomainIP(edit1.text) then
showmessage('Okay')
else
showmessage('NO! '+sErrorWAS);
end;
end.
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