whats new ¦  programming tips ¦  indy articles ¦  intraweb articles ¦  informations ¦  links ¦  interviews
 misc ¦  tutorials ¦  Add&Win Game

Tips (1541)

Database (90)
Files (137)
Forms (107)
Graphic (114)
IDE (21)
Indy (5)
Internet / LAN (130)
IntraWeb (0)
Math (76)
Misc (126)
Multimedia (45)
Objects/
ActiveX (51)

OpenTools API (3)
Printing (35)
Strings (83)
System (266)
VCL (242)

Top15

Tips sort by
component


Search Tip

Add new Tip

Add&Win Game

Advertising

44 Visitors Online


 
...determine if a Comm Port is available?
Autor: Jorge A. Canevaro
[ Print tip ]  

Tip Rating (17):  
     


{
  This tip uses the API of Windows to determine
  if a this available certain COM.
  Port: COM1, COM2, COM3...
}

function ComPortAvailable(Port: PChar): Boolean;
var
  
DeviceName: array[0..80] of Char;
  ComFile: THandle;
begin
  
StrPCopy(DeviceName, Port);

  ComFile := CreateFile(DeviceName, GENERIC_READ or GENERIC_WRITE, 0, nil,
    OPEN_EXISTING,
    FILE_ATTRIBUTE_NORMAL, 0);

  Result := ComFile <> INVALID_HANDLE_VALUE;
  CloseHandle(ComFile);
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if 
ComPortAvailable('COM1:') then
    
ShowMessage('Port available')
  else
    
ShowMessage('Port not available');
end;


 

Rate this tip:

poor
very good


Copyright © by SwissDelphiCenter.ch
All trademarks are the sole property of their respective owners