XPath-js.html

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>XPath</title>
</head>
<body>
<h2>Herodotus</h2>

<div id="example">
</div>

<script type="text/javascript">

(function(){

if (!('XPathEvaluator' in window)) {
	console.log('XPath does not appear to be available in this browser. Please try another.');
	return;
}

if(!('fetch' in window)) {
	  console.log('Fetch does not appear to be available in this browser. Please try another.');
	  return;
}

if(!('DOMParser' in window)){
	  console.log('DOMParser does not appear to be available in this browser. Please try another.');
	  return;
}


loadFile("data/Perseus_text_1999.01.0126.xml").then(data => {
	
	const parser = new DOMParser();
	const xml = parser.parseFromString(data, "application/xml");
	
	let xpath = xml.evaluate('//div1[@type="Book" and @n=1]//milestone[@unit="chapter"]', xml, null, XPathResult.ANY_TYPE, null);
	let output = []; 

	try {
	  let node = xpath.iterateNext();
	  while (node) {
        output.push(node.attributes[1]);
	    node = xpath.iterateNext();
	  }
	}
	catch (e) {
	  alert( 'Error: Document tree modified during iteration ' + e );
	}
	
	const example = document.getElementById("example");
	example.innerHTML = output.join();
});

async function loadFile(filepath){
	
	const response = await fetch(filepath);
	if(!response.ok){
		console.log('Looks like there was a problem: ', response.status);
		return;
	}
	const text = await response.text();
	return text;
}

})();

</script>
</body>
</html>