ondragstart Event

DOM Events DragEvent

Definition and Usage

The ondragstart event occurs when the user starts dragging an element or text selection.

Drag-and-drop is a very common feature in HTML5. It is when you 'grab' an object and drag it to a different location. For more information, please read our HTML5 Drag and DropHTML tutorial.

Note:To make an element draggable, use the global HTML5 draggable attribute.

Tip:By default, links and images are draggable without the draggable attribute.

Many events are used at different stages of the drag-and-drop operation, and may occur:

Events triggered on the draggable target (source element):

  • ondragstart - Occurs when the user starts dragging the element
  • ondrag - Occurs when the element is being dragged
  • ondragend - Occurs when the user completes dragging the element

Events triggered on the drop target:

  • ondragenter - Occurs when the dragged element enters the drop target
  • ondragover - Occurs when the dragged element is on the drop target
  • ondragleave - Occurs when the dragged element leaves the drop target
  • ondrop - Occurs when the dragged element is placed on the drop target

Example

Execute JavaScript when the user starts dragging a <p> element:

<p draggable="true" ondragstart="myFunction(event)">Drag me!</p>

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More TIY examples are available at the bottom of the page.

Syntax

In HTML:

<element ondragstart="myScript">

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In JavaScript:

object.ondragstart = function(){myScript};

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In JavaScript, use the addEventListener() method:

object.addEventListener("dragstart", myScript);

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Note:Internet Explorer 8 or earlier versions do not support addEventListener() method.

Technical details

Bubble: Supported
Cancelable: Supported
Event type: DragEvent
Supported HTML tags: All HTML elements
DOM version: Level 3 Events

Browser support

The numbers in the table indicate the first browser version that fully supports the event.

Event Chrome IE Firefox Safari Opera
ondragstart 4.0 9.0 3.5 6.0 12.0

More examples

Demonstration of all possible drag and drop events:

<p draggable="true" id="dragtarget">Drag me!</p>
<div class="droptarget">Drop here!</div>
<script>
/* ----------------- Events triggered on the drag target ----------------- */
document.addEventListener("dragstart", function(event) {
  // The dataTransfer.setData() method sets the data type and value of the data being dragged
  event.dataTransfer.setData("Text", event.target.id);
  // Output some text when the p element starts to be dragged
  document.getElementById("demo").innerHTML = "Started to drag the p element.";
  // Change the opacity of the draggable element
  event.target.style.opacity = "0.4";
});
// Change the output text color when dragging the p element
document.addEventListener("drag", function(event) {
  document.getElementById("demo").style.color = "red";
});
// After the p element is dragged, output some text and reset the opacity
document.addEventListener("dragend", function(event) {
  document.getElementById("demo").innerHTML = "Finished dragging the p element.";
  event.target.style.opacity = "1";
});
/* ----------------- Events triggered on the drop target ----------------- */
// Change the DIV border style when the draggable p element enters the droptarget
document.addEventListener("dragenter", function(event) {
  if ( event.target.className == "droptarget" ) {
    event.target.style.border = "3px dotted red";
  }
});
// By default, data/elements cannot be placed in other elements. To allow placement, we must prevent the element's default handling
document.addEventListener("dragover", function(event) {
  event.preventDefault();
});
// Reset the DIV border style when the draggable p element leaves the droptarget
document.addEventListener("dragleave", function(event) {
  if ( event.target.className == "droptarget" ) {
    event.target.style.border = "";
  }
});
/* On drop - Prevent the browser's default handling of data (open links by default when dropped) */
Reset the output text color and the DIV border color
Use the dataTransfer.getData() method to get the dragged data
The dragged data is the id of the draggable element ("drag1")
Attach the draggable element to the drop element
*/
document.addEventListener("drop", function(event) {
  event.preventDefault();
  if ( event.target.className == "droptarget" ) {
    document.getElementById("demo").style.color = "";
    event.target.style.border = "";
    var data = event.dataTransfer.getData("Text");
    event.target.appendChild(document.getElementById(data));
  }
});
</script>

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Related Pages

HTML Tutorial: HTML5 Drag and Drop

HTML Reference Manual: HTML draggable attribute

DOM Events DragEvent