DOMParser: parseFromString() method

string

The string to be parsed. It must contain either an HTML, xml, XHTML, or svg document.

mimeType

A string. This string determines whether the XML parser or the HTML parser is used to parse the string. Valid values are:

• text/html
• text/xml
• application/xml
• application/xhtml+xml
• image/svg+xml

A value of text/html will invoke the HTML parser, and the method will return an HTMLDocument. Any <script> element gets marked non-executable, and the contents of <noscript> are parsed as markup.

The other valid values (text/xml, application/xml, application/xhtml+xml, and image/svg+xml) are functionally equivalent. They all invoke the XML parser, and the method will return a XMLDocument.

Any other value is invalid and will cause a TypeError to be thrown.

An HTMLDocument or an XMLDocument, depending on the mimeType argument.

Note that a MIME type of text/html will invoke the HTML parser, and any other valid MIME type will invoke the XML parser. The application/xml and image/svg+xml MIME types in the example below are functionally identical — the latter does not include any SVG-specific parsing rules. Distinguishing between the two serves only to clarify the code's intent.

const parser = new DOMParser();

const xmlString = "<warning>Beware of the tiger</warning>";
const doc1 = parser.parseFromString(xmlString, "application/xml");
// XMLDocument

const svgString = '<circle cx="50" cy="50" r="50"/>';
const doc2 = parser.parseFromString(svgString, "image/svg+xml");
// XMLDocument

const htmlString = "<strong>Beware of the leopard</strong>";
const doc3 = parser.parseFromString(htmlString, "text/html");
// HTMLDocument

console.log(doc1.documentElement.textContent);
// "Beware of the tiger"

console.log(doc2.firstChild.tagName);
// "circle"

console.log(doc3.body.firstChild.textContent);
// "Beware of the leopard"

When using the XML parser with a string that doesn't represent well-formed XML, the XMLDocument returned by parseFromString will contain a <parsererror> node describing the nature of the parsing error.

const parser = new DOMParser();

const xmlString = "<warning>Beware of the missing closing tag";
const doc = parser.parseFromString(xmlString, "application/xml");
const errorNode = doc.querySelector("parsererror");
if (errorNode) {
  // parsing failed
} else {
  // parsing succeeded
}

Additionally, the parsing error may be reported to the browser's JavaScript console.

• XMLSerializer
• JSON.parse() - counterpart for JSON documents.