DataTransferItemList: remove() method

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

The DataTransferItemList.remove() method removes the DataTransferItem at the specified index from the list. If the index is less than zero or greater than one less than the length of the list, the list will not be changed.

Syntax

remove(index)

Parameters

index: The zero-based index number of the item in the drag data list to remove. If the index doesn't correspond to an existing item in the list, the list is left unchanged.

Return value

None (undefined).

Exceptions

InvalidStateError DOMException: Thrown if the drag data store is not in read/write mode and so the item cannot be removed.

Examples

Dragging and dropping an element

This example shows the use of the remove() method.

HTML

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>

CSS

css

div {
  margin: 0em;
  padding: 2em;
}

#source {
  color: blue;
  border: 1px solid black;
}

#target {
  border: 1px solid black;
}

JavaScript

function dragstart_handler(ev) {
  console.log("dragStart");
  // Add this element's id to the drag payload so the drop handler will
  // know which element to add to its tree
  const dataList = ev.dataTransfer.items;
  dataList.add(ev.target.id, "text/plain");
  // Add some other items to the drag payload
  dataList.add("<p>Paragraph…</p>", "text/html");
  dataList.add("http://www.example.org", "text/uri-list");
}

function drop_handler(ev) {
  console.log("Drop");
  ev.preventDefault();
  const data = event.dataTransfer.items;
  // Loop through the dropped items and log their data
  for (const item of data) {
    if (item.kind === "string" && item.type.match("^text/plain")) {
      // This item is the target node
      item.getAsString((s) => {
        ev.target.appendChild(document.getElementById(s));
      });
    } else if (item.kind === "string" && item.type.match("^text/html")) {
      // Drag data item is HTML
      item.getAsString((s) => {
        console.log(`… Drop: HTML = ${s}`);
      });
    } else if (item.kind === "string" && item.type.match("^text/uri-list")) {
      // Drag data item is URI
      item.getAsString((s) => {
        console.log(`… Drop: URI = ${s}`);
      });
    }
  }
}

function dragover_handler(ev) {
  console.log("dragOver");
  ev.preventDefault();
  // Set the dropEffect to move
  ev.dataTransfer.dropEffect = "move";
}

function dragend_handler(ev) {
  console.log("dragEnd");
  const dataList = ev.dataTransfer.items;
  // Clear all the files. Iterate in reverse order to safely remove.
  for (let i = dataList.length - 1; i >= 0; i--) {
    if (dataList[i].kind === "file") {
      dataList.remove(i);
    }
  }
  // Clear any remaining drag data
  dataList.clear();
}

const source = document.querySelector("#source");
source.addEventListener("dragstart", dragstart_handler);
source.addEventListener("dragend", dragend_handler);

const target = document.querySelector("#target");
target.addEventListener("drop", drop_handler);
target.addEventListener("dragover", dragover_handler);

Result

Specifications

Specification
HTML Standard # dom-datatransferitemlist-remove-dev

Browser compatibility

BCD tables only load in the browser