The DataTransferItemList.add()
method creates a new DataTransferItem
using the specified data and adds it to the drag data list. The item may be a File
or a string
of a given type. If the item is successfully added to the list, the newly-created DataTransferItem
object is returned.
Syntax
DataTransferItem = DataTransferItemList.add(data, type); DataTransferItem = DataTransferItemList.add(file);
Parameters
data
- A
string
representing the drag item's data. type
- A
string
of the drag item's type. Some example types aretext/html
andtext/plain
.
file
- A
File
object. No type needs to be given in this case.
Return value
A DataTransferItem
containing the specified data. If the drag item couldn't be created (for example, if the associated DataTransfer
object has no data store), null
is returned.
Exceptions
NotSupportedError
- A string
data
parameter was provided, and the list already contains an item whosekind
is "Plain Unicode string" and whose type is equal to the specified type parameter.
Example
This example shows the use of the add()
method.
HTML
<div>
<p id="source" ondragstart="dragstart_handler(event);" ondragend="dragend_handler(event);" 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" ondrop="drop_handler(event);" ondragover="dragover_handler(event);">Drop Zone</div>
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
var 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();
var data = event.dataTransfer.items;
// Loop through the dropped items and log their data
for (var i = 0; i < data.length; i++) {
if ((data[i].kind == 'string') && (data[i].type.match('^text/plain'))) {
// This item is the target node
data[i].getAsString(function (s){
ev.target.appendChild(document.getElementById(s));
});
} else if ((data[i].kind == 'string') && (data[i].type.match('^text/html'))) {
// Drag data item is HTML
data[i].getAsString(function (s){
console.log("... Drop: HTML = " + s);
});
} else if ((data[i].kind == 'string') && (data[i].type.match('^text/uri-list'))) {
// Drag data item is URI
data[i].getAsString(function (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");
var dataList = ev.dataTransfer.items;
for (var i = 0; i < dataList.length; i++) {
dataList.remove(i);
}
// Clear any remaining drag data
dataList.clear();
}
Result
[[../../../../../../../mdn.mozillademos.org/en-US/docs/Web/API/DataTransferItemList/add%24samples/Examplef222|Result link]]
Specifications
Specification | Status | Comment |
HTML Living StandardThe definition of 'add()' in that specification. | Living Standard | |
HTML 5.1The definition of 'add()' in that specification. | Recommendation | Not included in W3C HTML5 Recommendation |
Browser compatibility
The compatibility table on this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.
Update compatibility data on GitHub
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
add
|
Chrome
Full support 13 |
Edge
No support 12 — 79 |
Firefox
Full support 50 |
IE
No support No |
Opera
Full support 12 |
Safari
Full support 6 |
WebView Android
Full support 4.4 |
Chrome Android
Full support 18 |
Firefox Android
Full support 50 |
Opera Android
No support No |
Safari iOS
Full support 6 |
Samsung Internet Android
Full support 1.0 |
Legend
- Full support
- Full support
- No support
- No support
DataTransferItemList.add() by Mozilla Contributors is licensed under CC-BY-SA 2.5.