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Node: isDefaultNamespace() method - Web APIs | MDN
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Node: isDefaultNamespace() method
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The isDefaultNamespace() method of the Node interface accepts a namespace URI as an argument.
It returns a boolean value that is true if the namespace is the default namespace on the given node and false if not.
Note:
The default namespace of an HTML element is always "". For a SVG element, it is set by the xmlns attribute.
Syntax
js
isDefaultNamespace(namespaceURI)
Parameters
namespaceURI-
A string representing the namespace against which the element will be checked.
Note:
namespaceURIis not an optional parameter, but can benull.
Return value
A boolean value that holds the return value true or false, indicating if the parameter is the default namespace, or not.
Example
html
Is "" the default namespace for <output>:
<output>Not tested</output>.<br />
Is "https://www.w3.org/2000/svg" the default namespace for <output>:
<output>Not tested</output>.<br />
Is "" the default namespace for <svg>: <output>Not tested</output>.<br />
Is "https://www.w3.org/2000/svg" the default namespace for <svg>:
<output>Not tested</output>.<br />
<svg xmlns="https://www.w3.org/2000/svg" height="1"></svg>
<button>Click to run tests</button>
js
const button = document.querySelector("button");
button.addEventListener("click", () => {
const htmlElt = document.querySelector("output");
const svgElt = document.querySelector("svg");
const result = document.getElementsByTagName("output");
result[0].value = htmlElt.isDefaultNamespace(""); // true
result[1].value = htmlElt.isDefaultNamespace("https://www.w3.org/2000/svg"); // false
result[2].value = svgElt.isDefaultNamespace(""); // false
result[3].value = svgElt.isDefaultNamespace("https://www.w3.org/2000/svg"); // true
});
Specifications
| Specification |
|---|
| DOM # dom-node-isdefaultnamespace |
Browser compatibility
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