The HTML DOM ondragover event occurs when a draggable element is being dragged over a valid dropzone.
Note: Links and images are draggable by default.
There are some events that are used and occurred in the different stages of a drag-and-drop operation:
- ondragstart: occurs when dragging of an element started.
- ondrag: occurs while an element is dragging.
- ondragend: occurs when dragging of an element finished.
- ondragenter: occurs when the dragged element entered into the drop target.
- ondragover: occurs when the dragged element is over the drop target.
- ondragleave: occurs when the dragged element leaves from the drop target.
- ondrop: occurs when the dragged element is dropped on the drop target.
Note: the ondragover event fires every 350 milliseconds while dragging an element.
Syntax:
- In HTML:
<element ondragover="myScript">
- In JavaScript:
object.ondragover = function(){myScript};- In JavaScript, using the addEventListener() method:
object.addEventListener("dragover", myScript);Example: Using HTML.
HTML
<!DOCTYPE HTML><html>
<head>
<style>
#droptarget {
float: center;
width: 300px;
height: 50px;
margin: 20px;
margin-top: 30px;
padding: 5px;
border: 6px solid green;
}
</style>
</head>
<body>
<h1 style="color:green">
GeeksforGeeks
</h1>
<h2>
HTML DOM ondragover Event
</h2>
<p ondragstart="dragStartEle(event)"
draggable="true" id="dragtarget">
Draggable element
</p>
<div id="droptarget"
ondrop="dropEle(event)"
ondragover="allowDropEle(event)">
</div>
<p id="try"></p>
<script>
function dragStartEle(event) {
event.dataTransfer.setData(
"Text", event.target.id);
}
function allowDropEle(event) {
event.preventDefault();
document.getElementById(
"try").innerHTML =
"Element is over the dropzone";
event.target.style.border = "6px dotted green";
}
function dropEle(event) {
event.preventDefault();
let data =
event.dataTransfer.getData("Text");
event.target.appendChild(
document.getElementById(data));
document.getElementById(
"try").innerHTML = "Dragging finished";
}
</script>
</body>
</html>
|
Output:
Example: Using JavaScript
HTML
<!DOCTYPE HTML><html>
<head>
<style>
#droptarget {
float: center;
width: 300px;
height: 50px;
margin: 20px;
margin-top: 30px;
padding: 5px;
border: 6px solid green;
}
</style>
</head>
<body>
<h1 style="color:green">
GeeksforGeeks
</h1>
<h2>HTML DOM ondragover Event</h2>
<p draggable="true" id="dragtarget">
Draggable element
</p>
<div id="droptarget"></div>
<p id="demo"></p>
<script>
let drag = document.getElementById(
"dragtarget");
let drop = document.getElementById(
"droptarget");
// Events fired on the drag target
drag.ondragstart = function (event) {
event.dataTransfer.setData(
"Text", event.target.id);
};
drag.ondrag = function (event) {
document.getElementById(
"demo").innerHTML =
"Dragging starts";
};
// Events fired on the drop target
drop.ondragover = function (event) {
event.preventDefault();
document.getElementById(
"demo").innerHTML =
"Element is over the dropzone";
event.target.style.border =
"6px dotted green";
};
drop.ondrop = function (event) {
event.preventDefault();
let data =
event.dataTransfer.getData("Text");
event.target.appendChild(
document.getElementById(data));
document.getElementById(
"demo").innerHTML = "Dragging finished";
};
</script>
</body>
</html>
|
Output:
Example: Using the addEventListener() method
HTML
<!DOCTYPE HTML><html>
<head>
<style>
#droptarget {
float: center;
width: 300px;
height: 50px;
margin: 20px;
margin-top: 30px;
padding: 5px;
border: 6px solid green;
}
</style>
</head>
<body>
<h1 style="color:green">
GeeksforGeeks
</h1>
<h2>HTML DOM ondragover Event</h2>
<p draggable="true" id="dragtarget">
Draggable element
</p>
<div id="droptarget"></div>
<p id="try"></p>
<script>
let drag = document.getElementById(
"dragtarget");
let drop = document.getElementById(
"droptarget");
// Events fired on the drag target
drag.addEventListener(
"dragstart", function (event) {
event.dataTransfer.setData(
"Text", event.target.id);
});
drag.addEventListener(
"drag", function (event) {
document.getElementById(
"try").innerHTML = "Dragging starts";
});
// Events fired on the drop target
drop.addEventListener(
"dragover", function (event) {
event.preventDefault();
document.getElementById(
"try").innerHTML =
"Element is over the dropzone";
event.target.style.border =
"6px dotted green";
});
drop.addEventListener(
"drop", function (event) {
event.preventDefault();
let data =
event.dataTransfer.getData("Text");
event.target.appendChild(
document.getElementById(data));
document.getElementById(
"try").innerHTML =
"Dragging finished";
});
</script>
</body>
</html>
|
Output:
Supported Browsers: The browsers supported by HTML DOM ondragover Event are listed below:
- Google Chrome 1.0
- Edge 12.0
- Internet Explorer 9.0
- Firefox 9.0
- Apple Safari 3.1
- Opera 12.0