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GetKeyEvent function

In unit keyboard

Get the next raw key event, wait if needed.

Declaration

pascal
function GetKeyEvent: TKeyEvent

Description

GetKeyEvent returns the last keyevent if it is available, or waits for one if none is available. A non-blocking version is available in PollKeyEvent.

The returned key is encoded as a TKeyEvent type variable, and is normally the physical key scan code, (the scan code is driver dependent) which can be translated with one of the translation functions TranslateKeyEvent or TranslateKeyEventUniCode. See the types section for a description of how the key is described.

Errors

If no key became available (e.g. when the driver does not support it), 0 is returned.

See also

Example: ex1

pascal
program example1;

{ This program demonstrates the GetKeyEvent function }

uses keyboard;

Var
  K : TKeyEvent;

begin
  InitKeyBoard;
  Writeln('Press keys, press "q" to end.');
  Repeat
    K:=GetKeyEvent;
    K:=TranslateKeyEvent(K);
    Write('Got key event with ');
    Case GetKeyEventFlags(K) of
      kbASCII    : Writeln('ASCII key');
      kbUniCode  : Writeln('Unicode key');
      kbFnKey    : Writeln('Function key');
      kbPhys     : Writeln('Physical key');
      kbReleased : Writeln('Released key event');
    end;
    Writeln('Got key : ',KeyEventToString(K));
  Until (GetKeyEventChar(K)='q');
  DoneKeyBoard;
end.

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.