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DocumentType: systemId property - Web APIs | MDN
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DocumentType: systemId property
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 read-only systemId property of the DocumentType returns the URL of the associated DTD.
For synthetic DocumentType, this property reflects the value given in parameter to DOMImplementation.createDocumentType().
Value
A string.
Examples
js
const docType = document.implementation.createDocumentType(
"svg",
"",
"https://www.w3.org/2000/svg",
);
console.log(docType.systemId); // Displays "https://www.w3.org/2000/svg"
Specifications
| Specification |
|---|
| DOM # dom-documenttype-systemid |
Browser compatibility
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