Validate XML with JavaScript code

validateXML

var xt = "", h3OK = 1;
function checkErrorXML(x) {
  xt = "";
  h3OK = 1;
  checkXML(x);
}

function checkXML(n) {
  var l, i, nam;
  nam = n.nodeName;
  if (nam == "h3") {
    if (h3OK == 0) {
      return;
    }
    h3OK = 0;
  }
  if (nam == "#text") {
    xt = xt + n.nodeValue + "\n";
  }
  l = n.childNodes.length;
  for (i = 0; i < l; i++) {
    checkXML(n.childNodes[i]);
  }
}
function validateXML(xml) {
  // code for IE
  if (window.ActiveXObject) {
    var xmlDoc = new ActiveXObject("Microsoft.XMLDOM");
    xmlDoc.async = false;
    xmlDoc.loadXML(xml);

    if (xmlDoc.parseError.errorCode != 0) {
      txt = "Error Code: " + xmlDoc.parseError.errorCode + "\n";
      txt = txt + "Error Reason: " + xmlDoc.parseError.reason;
      txt = txt + "Error Line: " + xmlDoc.parseError.line;
      alert(txt);
    } else {
      alert("No errors found");
    }
  }
  // code for Chrome, Firefox etc.
  else if (document.implementation && document.implementation.createDocument) {
    var parser = new DOMParser();
    var text = xml;
    var xmlDoc = parser.parseFromString(text, "text/xml");
    if (xmlDoc.getElementsByTagName("parsererror").length > 0) {
      checkErrorXML(xmlDoc.getElementsByTagName("parsererror")[0]);
      alert(xt);
    } else {
      alert("No errors found");
    }
  } else {
    alert("Your browser cannot handle this script");
  }
}

var xml = "<xml><name>supun</name><age>23<year>1111</year></xml>";
validateXML(xml);