The DataTransfer.setData() method sets the drag operation's drag data to the specified data and type. If data for the given type does not exist, it is added at the end of the drag data store, such that the last item in the types list will be the new type. If data for the given type already exists, the existing data is replaced in the same position. That is, the order of the types list is not changed when replacing data of the same type.
Example data types are text/plain and text/uri-list.
In this example we can drag a <p> element into a target <div> element.
- In the
dragstart handler, we use setData() to add the id of the <p> element to the DataTransfer object. - In the
drop handler we retrieve the id and use it to move the <p> element into the target.
HTML
<div>
<p id="source" draggable="true">
Select this element, drag it to the drop zone and then release the selection
to move the element.
</p>
</div>
<div id="target">Drop Zone</div>
<button id="reset">Reset example</button>
CSS
div {
margin: 0.5em 0;
padding: 2em;
}
#target,
#source {
border: 1px solid black;
padding: 0.5rem;
}
.dragging {
background-color: pink;
}
JavaScript
const source = document.querySelector("#source");
source.addEventListener("dragstart", (ev) => {
console.log("dragStart");
ev.currentTarget.classList.add("dragging");
ev.dataTransfer.clearData();
ev.dataTransfer.setData("text/plain", ev.target.id);
});
source.addEventListener("dragend", (ev) =>
ev.target.classList.remove("dragging"),
);
const target = document.querySelector("#target");
target.addEventListener("dragover", (ev) => {
console.log("dragOver");
ev.preventDefault();
});
target.addEventListener("drop", (ev) => {
console.log("Drop");
ev.preventDefault();
const data = ev.dataTransfer.getData("text");
const source = document.getElementById(data);
ev.target.appendChild(source);
});
const reset = document.querySelector("#reset");
reset.addEventListener("click", () => document.location.reload());
Result