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HTML Drag and Drop API

In HTML, any element can be dragged and dropped.

Example

 

Memeph

 

Drag the MEMEPh image into the rectangle.

Drag and Drop

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

Browser Support

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

API
<Drag and Drop> 4.0 9.0 3.5 6.0 12.0

HTML Drag and Drop Example

The example below is a simple drag and drop example:

Example

<!DOCTYPE HTML>
<html>
<head>
<style>
#div1 {
  width: 350px;
  height: 70px;
  padding: 10px;
  border: 1px solid #aaaaaa;
}
</style>
<script>
function allowDrop(ev) {
  ev.preventDefault();
}

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

function drop(ev) {
  ev.preventDefault();
  var data = ev.dataTransfer.getData("text");
  ev.target.appendChild(document.getElementById(data));
}
</script>
</head>
<body>

<p>Drag the MEMEPh image into the rectangle:</p>

<div id="div1" ondrop="drop(event)" ondragover="allowDrop(event)"></div>
<br>
<img id="drag1" src="/cdn/logo/icon.jpg" draggable="true" ondragstart="drag(event)" width="106" height="69">

</body>
</html>

Try it Yourself »

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:

<img draggable="true">

What to Drag - ondragstart and setData()

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

In the example above, the ondragstart attribute calls a function, drag(event), that specifies what data to be dragged.

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

function drag(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 ("drag1").

Where to Drop - ondragover

The ondragover event 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 event.preventDefault() method for the ondragover event:

event.preventDefault()

Do the Drop - ondrop

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

In the example above, the ondrop attribute calls a function, drop(event):

function drop(ev) {
  ev.preventDefault();
  var data = ev.dataTransfer.getData("text");
  ev.target.appendChild(document.getElementById(data));
}

Code explained:

More Examples

Example

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

Drag and Drop

Drag the image back and forth between the two div elements.

 

Try it Yourself »

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