Home / comp / gb.qt / key / control 
Key.Control (gb.qt)
Syntax
STATIC PROPERTY READ Control AS Boolean
Returns if the CONTROL key is pressed.

This is inside ..._KeyPress or ..._KeyRelease Events.
Keys may have functions assigned to them by OS or other programs; you could close/... your program/other programs/system.

See also
  KeyPress  , KeyRelease 
Example
' Needing a Button1; with the focus on it( Use the Tab key).
' can cut and Paste this  example.

PUBLIC SUB Button1_KeyPress()
  IF Key.Control THEN
    Button1.Text = " True " & CString(Time)
  ELSE
    Button1.Text = " False " & CString(Time)
  ENDIF
END

Example
PUBLIC SUB Form_KeyPress()
' Control KeyPress event will often pass through to this Form event.
  DIM CntrlDown AS Boolean
  TRY CntrlDown = Key.Control
  CntrlDown = IIf( ERROR , FALSE, CntrlDown)
  IF CntrlDown THEN
    ME.Text = CString(Time) & " True: Control key is being held down"
  ELSE
    ME.Text = CString(Time) & " False: Control key was not held down"
  ENDIF
END