HTML ondragover Event Attribute - HTML Drag Events Attribute

The ondragover event attribute in HTML is a global event attribute that fires when a draggable element or text selection is being dragged over a valid drop target.

Example of HTML ondragover Event Attribute

It will Execute a JavaScript when an element is being dragged over a drop target.

index.html

Example: HTML

 <div ondragover="myFunction(event)"></div>

Output should be:

Definition and Usage of HTML ondragover Event Attribute

The ondragover attribute fires when a draggable element or text selection is being dragged over a valid drop target.

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 attribute.

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 event attributes 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 - fires when the user starts to drag an element
- ondrag - fires when an element is being dragged
- ondragend - fires when the user has finished dragging the element

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

Note: While dragging an element, the ondragover event fires every 350 milliseconds.

Browser Support of HTML ondragover Event Attribute

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

Syntax of HTML ondragover Event Attribute

<element ondragover="script">

Attribute Values of HTML ondragover Event Attribute

Value	Description
script	The script to be run on ondragover

Technical Details of HTML ondragover Event Attribute

Supported HTML tags:	ALL HTML elements

How to Execute a JavaScript when an element is being dragged over a drop target

It will Drag me into the rectangle.

index.html

Example: HTML

<!DOCTYPE HTML>
<html>
<head>
<style>
#droptarget {
  float: left; 
  width: 200px; 
  height: 35px;
  margin: 55px;
  margin-top: 155px;
  padding: 10px;
  border: 1px solid #aaaaaa;
}
</style>
</head>
<body>

<p ondragstart="dragStart(event)" draggable="true" id="dragtarget">Drag me into the rectangle!</p>

<div id="droptarget" ondrop="drop(event)" ondragover="allowDrop(event)">
</div>

<p style="clear:both;" id="demo"></p>

<script>
function dragStart(event) {
  event.dataTransfer.setData("Text", event.target.id);
}

function allowDrop(event) {
  event.preventDefault();
  document.getElementById("demo").innerHTML = "The p element is OVER the droptarget.";
  event.target.style.border = "4px dotted green";
}

function drop(event) {
  event.preventDefault();
  let data = event.dataTransfer.getData("Text");
  event.target.appendChild(document.getElementById(data));
  document.getElementById("demo").innerHTML = "The p element was dropped.";
}
</script>

</body>
</html>

Output should be:

html event attributes

Type:	Develop
Category:	Web Tutorial
Sub Category:	HTML Drag Events Attribute
Uploaded by:	Admin

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