JavaScript验证XML

/** * 支持chrome, firefox, ie的xml验证 */function validateXML(txt){// code for IEif (window.ActiveXObject){  var xmlDoc = new ActiveXObject("Microsoft.XMLDOM");  xmlDoc.async="false";  xmlDoc.loadXML(txt);  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);//Ext.Msg.alert("警告","XML验证错误！");return false;  }else{//alert("XML验证通过！");return true;  }}// code for Mozilla, Firefox, Opera, etc.else if (document.implementation.createDocument){var parser=new DOMParser();var xmlDoc=parser.parseFromString(txt,"text/xml");if (xmlDoc.documentElement.nodeName=="parsererror" || xmlDoc.documentElement.firstChild.nodeName=="parsererror"){//Ext.Msg.alert("警告","XML验证错误！");return false;}else{//alert("XML验证通过！");return true;}}}