Element: namespaceURI property
The Element.namespaceURI
read-only property returns the namespace URI of the element, or null
if the element is not in a namespace.
Value
A string, or null
.
Examples
In this snippet, an element is being examined for its localName
and its namespaceURI
. If the namespaceURI
returns the XUL namespace and the localName
returns "browser", then the node is understood to be a XUL <browser/>
.
if (
element.localName === "browser" &&
element.namespaceURI ===
"http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"
) {
// this is a XUL browser
}
Notes
This is not a computed value that is the result of a namespace lookup based on an examination of the namespace declarations in scope. The namespace URI of a node is frozen at the node creation time.
The namespace URI for HTML elements in HTML documents is http://www.w3.org/1999/xhtml
as in XHTML.
You can create an element with the specified namespaceURI
using the document.createElementNS()
method.
The DOM does not handle or enforce namespace validation per se. It is up to the DOM application to do any validation necessary. Also note that the namespace prefix, once it is associated with a particular element, cannot be changed.
Specifications
Specification |
---|
DOM Standard # ref-for-dom-element-namespaceuri① |
Browser compatibility
BCD tables only load in the browser