Name 

Description 

 

OnActivate 

Occurs when the form becomes active. 

 

OnAlignInsertBefore 

Occurs when an object with custom alignment is aligned. 

 

OnAlignPosition 

Occurs when an object with custom alignment is aligned. 

 

OnCanResize 

Occurs when an attempt is made to resize the control. 

 

OnCanResize 

Occurs when an attempt is made to resize the control. 

 

OnClick 

Occurs when the user clicks the control. 

 

OnClick 

Occurs when the user clicks the control. 

 

OnClose 

Occurs when the form closes. 

 

OnCloseQuery 

Occurs when close is attempted. 

 

OnConstrainedResize 

Adjust resize constraints. 

 

OnContextPopup 

Occurs when the user right-clicks the control or otherwise invokes the popup menu (such as using the keyboard). 

 

OnCreate 

Occurs when the form is created. 

 

OnDblClick 

Occurs when the user double-clicks the left mouse button when the mouse pointer is over the control. 

 

OnDblClick 

Occurs when the user double-clicks the left mouse button when the mouse pointer is over the control. 

 

OnDeactivate 

Occurs when the form loses focus. 

 

OnDestroy 

Occurs when the form is destroyed. 

 

OnDockDrop 

Occurs when another control is docked to the control. 

 

OnDockOver 

Occurs when another control is dragged over the control. 

 

OnDragDrop 

Occurs when the user drops an object being dragged. 

 

OnDragDrop 

Occurs when the user drops an object being dragged. 

 

OnDragOver 

Occurs when the user drags an object over a control. 

 

OnDragOver 

Occurs when the user drags an object over a control. 

 

OnEndDock 

Occurs when the dragging of an object ends, either by docking the object or by canceling the dragging. 

 

OnEndDrag 

Occurs when the dragging of an object ends, either by dropping the object or by canceling the dragging. 

 

OnEnter 

Occurs when a control receives the input focus. 

 

OnExit 

Occurs when the input focus shifts away from one control to another. 

 

OnGetSiteInfo 

Returns the control's docking information. 

 

OnHelp 

Occurs when the form receives a request for help. 

 

OnHide 

Occurs when the form is hidden (that is, when its Visible property is set to false). 

 

OnKeyDown 

Occurs when a user presses any key while the control has focus. 

 

OnKeyDown 

Occurs when a user presses any key while the control has focus. 

 

OnKeyPress 

Occurs when a key is pressed. 

 

OnKeyPress 

Occurs when a key is pressed. 

 

OnKeyUp 

Occurs when the user releases a key that has been pressed. 

 

OnKeyUp 

Occurs when the user releases a key that has been pressed. 

 

OnMouseActivate 

Occurs when the user presses a mouse button with the mouse pointer over a control and the parent form is not active. 

 

OnMouseActivate 

Occurs when the user presses a mouse button with the mouse pointer over a control and the parent form is not active. 

 

OnMouseDown 

Occurs when the user presses a mouse button with the mouse pointer over a control. 

 

OnMouseDown 

Occurs when the user presses a mouse button with the mouse pointer over a control. 

 

OnMouseEnter 

Occurs when the user moves the mouse into a control. 

 

OnMouseLeave 

Occurs when the user moves the mouse outside of a control. 

 

OnMouseMove 

Occurs when the user moves the mouse pointer while the mouse pointer is over a control. 

 

OnMouseMove 

Occurs when the user moves the mouse pointer while the mouse pointer is over a control. 

 

OnMouseUp 

Occurs when the user releases a mouse button that was pressed with the mouse pointer over a component. 

 

OnMouseUp 

Occurs when the user releases a mouse button that was pressed with the mouse pointer over a component. 

 

OnMouseWheel 

Occurs when the mouse wheel is rotated. 

 

OnMouseWheelDown 

Occurs when the mouse wheel is rotated downward. 

 

OnMouseWheelUp 

Occurs when the mouse wheel is rotated upward. 

 

OnPaint 

Occurs when the form is redrawn. 

 

OnResize 

Occurs immediately after the control is resized. 

 

OnResize 

Occurs immediately after the control is resized. 

 

OnShortCut 

Occurs when the user presses a key (before the OnKeyDown event). 

 

OnShow 

Occurs when the form is shown (that is, when its Visible property is set to true). 

 

OnStartDock 

Occurs when the user begins to drag a control with a DragKind of dkDock. 

 

OnStartDrag 

Occurs when the user begins to drag the control or an object it contains by left-clicking on the control and holding the mouse button down. 

 

OnUnDock 

Occurs when the application tries to undock a control that is docked to the windowed control.