HTML DOM createDocumentType() Method

The DOMImplementation createDocumentType() method returns a Doctype object which can either be used with DOMImplementation createDocument() method for document creation or can be put into the document.

Syntax:

var doctype = document.implementation.createDocumentType(qualifiedNameStr, publicId, systemId);

Parameters:

qualifiedNameStr: It is a DOMString containing the qualified name
publicId: It is a DOMString containing the PUBLIC identifier.
systemId: It is a DOMString containing the SYSTEM identifiers.

Return Value: This function returns DOMDocumentType node.

Example: In this example, we will create a document type using this method.

html

</html>
<!DOCTYPE HTML> 

<html>  

<head>

    <meta charset="UTF-8">

    <title>createDocumentType() method</title>

</head>   
 
<body style="text-align:center;">

    <h1 style="color:green;">  

     GeeksforGeeks

    </h1> 

    <p id="a"> 

    HTML | DOM createDocumentType() method

    </p>
 
    <button onclick = "Geeks()">

    Click Here

    </button>

    <script> 

        function Geeks(){

            var dt = 
document.implementation.createDocumentType(
'svg:svg', null, 
'http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd');

            console.log(dt);

            var doc = document.implementation.createDocument (
'http://www.w3.org/1999/xhtml', 'html', dt);

            var head = document.createElementNS(
'http://www.w3.org/1999/xhtml', 'head');

            head.setAttribute('id', 'headDoc');

            doc.documentElement.appendChild(head);

            var body = document.createElementNS(
'http://www.w3.org/1999/xhtml', 'body');

            body.setAttribute('id', 'bodyDoc');

            doc.documentElement.appendChild(body);

            console.log(doc);

        }

  </script> 

</body>   

</html>