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This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.
The ChildNode.before method inserts a set of Node or DOMString objects in the children list of this ChildNode's parent, just before this ChildNode. DOMString objects are inserted as equivalent Text nodes.
Syntax
[Throws, Unscopable] void ChildNode.before((Node or DOMString)... nodes);
Parameters
Exceptions
HierarchyRequestError: Node cannot be inserted at the specified point in the hierarchy.
Examples
Inserting an element
var parent = document.createElement("div");
var child = document.createElement("p");
parent.appendChild(child);
var span = document.createElement("span");
child.before(span);
console.log(parent.outerHTML);
// "<div><span></span><p></p></div>"
Inserting text
var parent = document.createElement("div");
var child = document.createElement("p");
parent.appendChild(child);
child.before("Text");
console.log(parent.outerHTML);
// "<div>Text<p></p></div>"
Inserting an element and text
var parent = document.createElement("div");
var child = document.createElement("p");
parent.appendChild(child);
var span = document.createElement("span");
child.before(span, "Text");
console.log(parent.outerHTML);
// "<div><span></span>Text<p></p></div>"
ChildNode.before() is unscopable
The before() method is not scoped into the with statement. See Symbol.unscopables for more information.
with(node) {
before("foo");
}
// ReferenceError: before is not defined
Specification
| Specification | Status | Comment |
|---|---|---|
| DOM The definition of 'ChildNode.before()' in that specification. |
Living Standard | Initial definition. |
Browser compatibility
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari |
|---|---|---|---|---|---|
| Basic support | ? | 49 (49) | ? | ? | ? |
| Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | ? | 49.0 (49) | ? | ? | ? |