This event occurs whenever an additional mouse button X1 is clicked.

property OnMouseX1Down: TVFMouseX1DownEvent Type;

__property TVFMouseX1DownEvent OnMouseX1Down;

event TVFMouseX1DownEvent Type OnMouseX1Down;

Event OnMouseX1Down As TVFMouseX1DownEvent

OnMouseX1Down

__property TVFMouseX1DownEvent OnMouseX1Down;

OnMouseX1Down

published OnMouseX1Down;