Latest web development tutorials
 

ondragstart Event

< Event Object

Example

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

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

More "Try it Yourself" examples below.


Definition and Usage

The ondragstart event occurs when the user starts to drag 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, see our HTML Tutorial on HTML5 Drag and Drop.

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

Tip: Links and images are draggable by default, and do not need the draggable attribute.

There are many events that are used, and can occur, in the different stages of a drag and drop operation:

  • Events fired on the draggable target (the source element):
    • ondragstart - occurs when the user starts to drag an element
    • ondrag - occurs when an element is being dragged
    • ondragend - occurs when the user has finished dragging the element

  • Events fired on the drop target:
    • ondragenter - occurs when the dragged element enters the drop target
    • ondragover - occurs when the dragged element is over the drop target
    • ondragleave - occurs when the dragged element leaves the drop target
    • ondrop - occurs when the dragged element is dropped on the drop target

Browser Support

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

Event
ondragstart 4.0 9.0 3.5 6.0 12.0

Syntax

In HTML:

<element ondragstart="myScript">
Try it Yourself »

In JavaScript:

object.ondragstart=function(){myScript};
Try it Yourself »

In JavaScript, using the addEventListener() method:

object.addEventListener("dragstart", myScript);
Try it Yourself »

Note: The addEventListener() method is not supported in Internet Explorer 8 and earlier versions.


Technical Details

Bubbles: Yes
Cancelable: Yes
Event type: DragEvent
Supported HTML tags: All HTML elements
DOM Version: Level 3 Events

Examples

More Examples

Example

A demonstration of ALL possible drag and drop events:

<p draggable="true" id="dragtarget">Drag me!</p>

<div class="droptarget">Drop here!</div>

<script>
/* ----------------- Events fired on the drag target ----------------- */

document.addEventListener("dragstart", function(event) {
    // The dataTransfer.setData() method sets the data type and the value of the dragged data
    event.dataTransfer.setData("Text", event.target.id);

    // Output some text when starting to drag the p element
    document.getElementById("demo").innerHTML = "Started to drag the p element.";

    // Change the opacity of the draggable element
    event.target.style.opacity = "0.4";
});

// While dragging the p element, change the color of the output text
document.addEventListener("drag", function(event) {
    document.getElementById("demo").style.color = "red";
});

// Output some text when finished dragging the p element and reset the opacity
document.addEventListener("dragend", function(event) {
    document.getElementById("demo").innerHTML = "Finished dragging the p element.";
    event.target.style.opacity = "1";
});


/* ----------------- Events fired on the drop target ----------------- */

// When the draggable p element enters the droptarget, change the DIVS's border style
document.addEventListener("dragenter", function(event) {
    if ( event.target.className == "droptarget" ) {
        event.target.style.border = "3px dotted red";
    }
});

// By default, data/elements cannot be dropped in other elements. To allow a drop, we must prevent the default handling of the element
document.addEventListener("dragover", function(event) {
    event.preventDefault();
});

// When the draggable p element leaves the droptarget, reset the DIVS's border style
document.addEventListener("dragleave", function(event) {
    if ( event.target.className == "droptarget" ) {
        event.target.style.border = "";
    }
});

/* On drop - Prevent the browser default handling of the data (default is open as link on drop)
Reset the color of the output text and DIV's border color
Get the dragged data with the dataTransfer.getData() method
The dragged data is the id of the dragged element ("drag1")
Append the dragged element into 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>
Try it Yourself »

Related Pages

HTML Tutorial: HTML5 Drag and Drop

HTML Reference: HTML draggable Attribute


Event Object Reference Event Object