HTMLSlotElement

The HTMLSlotElement interface of the Shadow DOM API enables access to the name and assigned nodes of an HTML <slot> element.

Properties

HTMLSlotElement.name

A string used to get and set the slot's name.

Methods

HTMLSlotElement.assign()

Sets the manually assigned nodes for this slot to the given nodes.

HTMLSlotElement.assignedNodes()

Returns a sequence of the nodes assigned to this slot, and if the flatten option is set to true, the assigned nodes of any other slots that are descendants of this slot. If no assigned nodes are found, it returns the slot's fallback content.

HTMLSlotElement.assignedElements()

Returns a sequence of the elements assigned to this slot (and no other nodes). If the flatten option is set to true, it also returns the assigned elements of any other slots that are descendants of this slot. If no assigned nodes are found, it returns the slot's fallback content.

Events

slotchange

Fired on an HTMLSlotElement instance (<slot> element) when the node(s) contained in that slot change.

Examples

The following snippet is taken from our slotchange example (see it live also).

let slots = this.shadowRoot.querySelectorAll('slot');
slots[1].addEventListener('slotchange', function(e) {
  let nodes = slots[1].assignedNodes();
  console.log('Element in Slot "' + slots[1].name + '" changed to "' + nodes[0].outerHTML + '".');
});

Here we grab references to all the slots, then add a slotchange event listener to the 2nd slot in the template — which is the one that keeps having its contents changed in the example.

Every time the element inserted in the slot changes, we log a report to the console saying which slot has changed, and what the new node inside the slot is.

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
HTMLSlotElement
53
79
63
No
40
10
53
53
63
41
10
6.0
assign
86
86
92
No
72
No
86
86
92
61
No
14.0
assignedElements
65
79
66
No
52
12.1
65
65
66
47
12.2
9.0
assignedNodes
53
79
63
No
40
10
53
53
63
41
10
6.0
name
53
79
63
No
40
10
53
53
63
41
10
6.0
slotchange_event
53
79
63
No
40
10.1
53
53
63
41
10.3
6.0

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/HTMLSlotElement