To Prevent the default vertical scrolling action, the event handler sets the Handled parameter to true. This event occurs when an object is dragged out of the control's bounds. The handler for this event receives an argument of type EventArgs. C# Event Kavramları bu dersimde bu konudan etraflıca bahsetmiştim. Basar https://www.csharpegitimi.com.tr/2024/05/csharp-mouse-click-kullanimi.html