OnDblClick event occurs when the user double-clicks the left mouse button when the mouse pointer is over the control.
We use the OnDblClick event to respond to mouse double-clicks.
OnDblClick is an event handler of type System.Classes.TNotifyEvent.
What is TNotifyEvent?
TNotifyEvent is used for events that do not require parameters.
The TNotifyEvent type is the type for events that have no event-specific parameters. These events simply notify the component that a specific event occurred. For example, OnClick, which is of type TNotifyEvent, notifies the control that a click event occurred on the control.
The Sender parameter is the object whose event handler is called. For example, with the OnClick event of a button, the Sender parameter is the button component that is clicked.
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