W3Schools Tryit Editor

<!DOCTYPE HTML>
<html>
<style>
#droptarget {
  width: 200px; 
  height: 45px;
  padding: 10px;
  border: 1px solid black;
}
</style>

<body>
<h1>HTML DOM Events</h1>
<h2>The ondragover Event</h2>

<p>Use the addEventListener() method to attach a "dragstart" and "drag" event to a p element, and a "dragover" and "drop" event to a div element.</p>

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

/* 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("demo").innerHTML = "The text is being dragged.";
});

/* Events fired on the drop target */
drop.addEventListener("dragover", function(event) {
  event.preventDefault();
  document.getElementById("demo").innerHTML = "The text is OVER the droptarget.";
  event.target.style.border = "4px dotted purple";
});

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

</body>
</html>

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<!DOCTYPE HTML><html><style>#droptarget {  width: 200px;   height: 45px;  padding: 10px;  border: 1px solid black;}</style>​<body><h1>HTML DOM Events</h1><h2>The ondragover Event</h2>​<p>Use the addEventListener() method to attach a "dragstart" and "drag" event to a p element, and a "dragover" and "drop" event to a div element.</p>​<p draggable="true" id="dragtarget">Drag me into the rectangle!</p>​<div id="droptarget"></div>​<p id="demo"></p>​<script>const drag = document.getElementById("dragtarget");const 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("demo").innerHTML = "The text is being dragged.";});​​/* Events fired on the drop target */drop.addEventListener("dragover", function(event) {  event.preventDefault();  document.getElementById("demo").innerHTML = "The text is OVER the droptarget.";  event.target.style.border = "4px dotted purple";});