OnKeyPress

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English (en)

Overview

The OnKeyPress event of an object allows you to check what key the user has pressed.

Note that this procedure handles printable characters only. Non-printable characters (e.g. control sequences) are handled by the OnKeyDown event.

Light bulb  Note: OnKeyPress doesn't support Unicode characters. If you need Unicode characters but no control characters, use OnUTF8KeyPress.

Example

uses
  ...LCLType, Dialogs, ...;
  ...  

procedure TMainForm.FormKeyPress(Sender: TObject; var Key: char);
begin
  case key of
    '0': ShowMessage('"0" key pressed');
    '1': ShowMessage('"1" key pressed');
    '2': ShowMessage('"2" key pressed');
  end;
  Key := #0; // Necessary for some widgetsets, e.g. Cocoa, in order to disable processing in subsequent elements.
end;

See also