Check for XML errors using JavaScript

Question

Question: How do I syntax-check my XML in modern browsers (anything but IE)?

I've seen a page on W3Schools which includes an XML syntax-checker. I don't know how it works, but I'd like to know how I may achieve the same behavior.

I've already performed many searches on the matter (with no success), and I've tried using the DOM Parser to check if my XML is "well-formed" (also with no success).

 var xml = 'Caleb'; var parser = new DOMParser(); var doc = parser.parseFromString(xml, 'text/xml'); 

I expect the parser to tell me I have an XML syntax error (i.e. an unclosed name tag). However, it always returns an XML DOM object, as if there were no errors at all.

To summarize, I would like to know how I can automatically check the syntax of an XML document using JavaScript.

P.S. Is there any way I can validate an XML document against a DTD (using JS, and not IE)?

Answer 1

Edit: Here is a more concise example, from MDN:

var xmlString = '<a id="a"><b id="b">hey!</b></a>'; var domParser = new DOMParser(); var dom = domParser.parseFromString(xmlString, 'text/xml');  // print the name of the root element or error message dump(dom.documentElement.nodeName == 'parsererror' ? 'error while parsing' : dom.documentElement.nodeName); 

Answer 2

NoBugs answer above did not work with a current chrome for me. I suggest:

var sMyString = "<a id=\"a\"><b id=\"b\">hey!<\/b><\/a>"; var oParser = new DOMParser(); var oDOM = oParser.parseFromString(sMyString, "text/xml"); dump(oDOM.getElementsByTagName('parsererror').length ?       (new XMLSerializer()).serializeToString(oDOM) : "all good"     );