DataTransferItemList.clear()
The DataTransferItemList
method
clear()
removes all DataTransferItem
objects from the drag data items list, leaving the list empty.
The drag data store in which this list is kept is only writable while handling the
dragstart
event. While handling drop
, the drag data store is
in read-only mode, and this method silently does nothing. No exception is thrown.
Syntax
DataTransferItemList.clear();
Parameters
None.
Return value
Example
This example shows the use of the clear()
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
Result linkSpecifications
Specification |
---|
HTML Standard # dom-datatransferitemlist-clear-dev |
Browser compatibility
BCD tables only load in the browser