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Drag'n'Drop with mouse events

UI Events: Drag'n'Drop with mouse events


When a drag occurs, which event fires when the mouse moves over an element?

View Answer:
Interview Response: The dragover event is triggered as the mouse moves over an element when a drag occurs. The operation during an event is frequently the same as the dragenter event. The dragenter event occurs when a draggable element enters a drop target. A dragleave event occurs when the valid drop target is left. Dragstart gets dispatched whenever a user begins to drag an element.

How do you make content inside the browser draggable?

View Answer:
Interview Response: HTML5 includes a drag-and-drop feature. Setting the draggable property of an element to true makes it draggable.

HTML Example:

<!DOCTYPE html>
<html>
<head>
<title>Draggable Element</title>
</head>
<body>
<button draggable="true">Draggable Button</button>
<button>Normal Button</button>
</body>
</html>


What occurs when a drag action on an element begins?

View Answer:
Interview Response: There are three factors to remember when a drag event begins: the main points.

  • Drag Data: The data type gets sent while dragging occurs.
  • Drag Feedback: This image shows alongside the mouse pointer during a drag action.
  • Drag Effect: This describes the drag that occurs on an element. There are three categories, which are listed below.
  • Copy: The data dragged gets copied from its current position to the drop destination if this effect is enabled.
  • Move: This effect indicates that the dragged data is relocating from its original location to the drop destination.
  • Link: This effect suggests that a link or relationship between the source and drop sites gets established.


Can you list a few JavaScript drag-and-drop events associated with a callback method?

View Answer:
Interview Response: Seven possible drag and drop events can be programmatically associated with a callback method. They include drag, dragstart, dragenter, dragover, dragleave, drop, and dragend.

  • drag: The drag event triggers every hundred milliseconds as a user drags an object or text selection.
  • dragstart: When a drag starts, it fires on an element.
  • dragenter: this event is triggered when the mouse enters an element while dragging.
  • dragover: When a drag occurs, this event is triggered when the mouse moves over an element.
  • dragleave: This event is triggered when the mouse departs an element while it gets dragged.
  • drop: After the drag operation, the drop event fires on the element where the drop occurred.
  • dragend: When the drag operation finishes, whether it was successful, the drag source receives the dragend event.


What exactly is the dataTransfer property?

View Answer:
Interview Response: The dataTransfer object contains the data transmitted in a drag action. The dragstart event sets dataTransfer, which is read/handled in the drop event.