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Document: createAttribute() 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 createAttribute() method of the Document interface creates a new attribute node.
The object created is a node implementing the Attr interface.
The DOM does not enforce what sort of attributes can be added to a particular element in this manner.
Note:
The string given in parameter is converted to lowercase.
js
createAttribute(localName)
localName-
A string containing the name of the attribute.
The value is used to initialize the new attribute's localName property.
InvalidCharacterError DOMException-
Thrown if the localName value is not a valid attribute name.
It must have at least one character, and may not contain ASCII whitespace, NULL, /, = or > (U+0000, U+002F, U+003D, or U+003E, respectively).
Note:
Earlier versions of the specification were more restrictive, requiring that the localName be a valid XML name.
js
const node = document.getElementById("div1");
const a = document.createAttribute("my_attrib");
a.value = "newVal";
node.setAttributeNode(a);
console.log(node.getAttribute("my_attrib")); // "newVal"