Drag and Drop API

The HTML Drag and Drop API enables an element to be dragged and dropped.

Drag and drop is a very common feature. It is when you "grab" an object and drag it to a different location.

Drag the EA Academy image into the second rectangle.

Browser Support

The numbers in the table specify the first browser version that fully supports Drag and Drop API.

Drag and Drop API Example

The example below is a simple drag and drop example:

Example

It might seem complicated, but lets go through all the different parts of a drag and drop event.

Make an Element Draggable

First of all: To make an element draggable, set the draggable attribute to true:

or:

What to Drag - ondragstart and setData()

Then, specify what should happen when the element is dragged.

In the example above, the ondragstart attribute of the <img> element calls a function (dragstartHandler(ev)), that specifies what data to be dragged.

The dataTransfer.setData() method sets the data type and the value of the dragged data:

function dragstartHandler(ev) {
  ev.dataTransfer.setData("text",
  ev.target.id);
}

In this case, the data type is "text" and the value is the id of the draggable element ("img1").

Where to Drop - ondragover

The ondragover attrribute of the <div> element calls a function (dragoverHandler(ev)), that specifies where the dragged data can be dropped.

By default, data/elements cannot be dropped in other elements. To allow a drop, we must prevent the default handling of the element.

This is done by calling the preventDefault() method for the ondragover event:

function dragoverHandler(ev) {
  ev.preventDefault();
}

Do the Drop - ondrop

When the dragged data is dropped, a drop event occurs.

In the example above, the ondrop attribute of the <div> element calls a function, dropHandler(event):

function dropHandler(ev) {
  ev.preventDefault();
  const
   data = ev.dataTransfer.getData("text");
  ev.target.appendChild(document.getElementById(data));

   }

Code explained:

• Call preventDefault() to prevent the browser default handling of the data (default is open as link on drop)

• Get the dragged data with the dataTransfer.getData() method. This method will return any data that was set to the same type in the setData() method

• The dragged data is the id of the dragged element ("img1")

• Append the dragged element into the drop element

More Examples

Example

Example

Example

How to drag and drop an image back and forth between two <div> elements: