unit Dialer;

interface

uses

 SysUtils, WinTypes, WinProcs, Messages, Classes, Graphics, Controls,

 Forms, Dialogs;

type

 TComPort = (dpCOM1,dpCOM2,dpCOM3,dpCOM4);

 TMethod  = (dmTone,dmPulse);

 TDialer = class(TComponent)

 private

   { Private declarations }

   FComPort : TComPort;

   FNumberToDial : string;

   FConfirm : boolean;

   FMethod : TMethod;

 protected

   { Protected declarations }

 public

   { Public declarations }

   procedure Execute;

 published

   property ComPort : TComPort read FComPort

                write FComPort;

   property Confirm : boolean read FConfirm

                write FConfirm;

   property Method  : TMethod read FMethod

                write FMethod;

   property NumberToDial : string read FNumberToDial

                write FNumberToDial;

   { Published declarations }

 end;

procedure Register;

implementation

procedure Register;

begin

 RegisterComponents('Samples', [TDialer]);

end;

procedure TDialer.Execute;

var

 s : string;

 CId : Integer;

 Status : Integer;

 Buf : array[1..32] of Char;

begin

 if FConfirm then

 begin

  if MessageDlg('About to dial the number '+FNumberToDial+'. Are you sure?',

     mtConfirmation, [mbYes,mbNo], 0)=mrNo then Exit;

 end;

 {Create a string to send to modem}

 s:=Concat('ATDT',FNumberToDial,^M^J);

 if FMethod=dmPulse then s[4]:='P';

 {Open Com Port}

 StrPCopy(@Buf,'COM ');

 Buf[4]:=Chr(49+Ord(FComPort));

 CId:=OpenComm(@Buf,512,512);

 if CId<0 then

 begin

   MessageDlg('Unable to open '+StrPas(@Buf),mtError,

               [mbOk], 0);

   Exit;

 end;

 {Send phone number to modem}

 StrPCopy(@Buf,s);

 Status:=WriteComm(CId,@Buf,StrLen(@Buf));

 if Status>=0 then

 begin

   MessageDlg('Pick up the phone',mtInformation,

               [mbOk], 0);

   WriteComm(CId,'ATH'^M^J,5);

 end

 else

   MessageDlg('Unable to dial number',mtError,

               [mbOk], 0);

 {Close communication port}

 CloseComm(CId);

end;

end.

使用举例：

procedure TForm1.Button1Click(Sender: TObject);

var

 TempDialer : TDialer;

begin

 TempDialer:=TDialer.Create(Self);

 with TempDialer do

 begin

   ComPort:=dpCom4;

   Confirm:=true;

   Method:=dmTone;

   NumberToDial:='1(222)333-4444';

   Execute;

   Free;

 end;

end;