The DataTransfer.dropEffect
property controls the feedback (typically visual) the user is given during a drag and drop operation. It will affect which cursor is displayed while dragging. For example, when the user hovers over a target drop element, the browser's cursor may indicate which type of operation will occur.
When the DataTransfer
object is created, dropEffect
is set to a string value. On getting, it returns its current value. On setting, if the new value is one of the values listed below, then the property's current value will be set to the new value and other values will be ignored.
For the dragenter
and dragover
events, dropEffect
will be initialized based on what action the user is requesting. How this is determined is platform specific, but typically the user can press modifier keys such as the alt key to adjust the desired action. Within event handlers for dragenter
and dragover
events, dropEffect
should be modified if a different action is desired than the action that the user is requesting.
For the drop
and dragend
events, dropEffect
will be set to the action that was desired, which will be the value dropEffect
had after the last dragenter
or dragover
event. In a dragend
event, for instance, if the desired dropEffect is "move", then the data being dragged should be removed from the source.
Syntax
dataTransfer.dropEffect;
Values
A DOMString
representing the drag operation effect. The possible values are:
copy
- A copy of the source item is made at the new location.
move
- An item is moved to a new location.
link
- A link is established to the source at the new location.
none
- The item may not be dropped.
Assigning any other value to dropEffect
has no effect and the old value is retained.
Example
This example shows the use of the dropEffect
and effectAllowed
properties.
HTML Content
<div>
<p id="source" ondragstart="dragstart_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 Content
div {
margin: 0em;
padding: 2em;
}
#source {
color: blue;
border: 1px solid black;
}
#target {
border: 1px solid black;
}
JavaScript Content
function dragstart_handler(ev) {
console.log("dragStart: dropEffect = " + ev.dataTransfer.dropEffect + " ; effectAllowed = " + ev.dataTransfer.effectAllowed);
// Add this element's id to the drag payload so the drop handler will
// know which element to add to its tree
ev.dataTransfer.setData("text", ev.target.id);
ev.dataTransfer.effectAllowed = "move";
}
function drop_handler(ev) {
console.log("drop: dropEffect = " + ev.dataTransfer.dropEffect + " ; effectAllowed = " + ev.dataTransfer.effectAllowed);
ev.preventDefault();
// Get the id of the target and add the moved element to the target's DOM
var data = ev.dataTransfer.getData("text");
ev.target.appendChild(document.getElementById(data));
}
function dragover_handler(ev) {
console.log("dragOver: dropEffect = " + ev.dataTransfer.dropEffect + " ; effectAllowed = " + ev.dataTransfer.effectAllowed);
ev.preventDefault();
// Set the dropEffect to move
ev.dataTransfer.dropEffect = "move"
}
Specifications
Specification | Status | Comment |
HTML Living StandardThe definition of 'dropEffect' in that specification. | Living Standard | |
HTML 5.1The definition of 'dropEffect' in that specification. | Recommendation | Initial definition |
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 | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
dropEffect
|
Chrome
Full support Yes |
Edge
Full support 12 |
Firefox
Full support Yes |
IE
? |
Opera
Full support Yes |
Safari
Full support Yes |
WebView Android
Full support Yes |
Chrome Android
Full support Yes |
Firefox Android
Full support Yes |
Opera Android
Full support Yes |
Safari iOS
No support No |
Samsung Internet Android
Full support Yes |
Legend
- Full support
- Full support
- No support
- No support
- Compatibility unknown
- Compatibility unknown
See also
- Drag and drop
- Drag Operations
- Recommended Drag Types
- Dragging and Dropping Multiple Items
- DataTransfer test - Paste or Drag
DataTransfer.dropEffect by Mozilla Contributors is licensed under CC-BY-SA 2.5.