使用原始Javascript加载XML

Posted 2021-02-26

/*
	Author: Alvin Crespo
	Description: XMLLoader
*/
 
//xml object variable
var xmlhttp;
 
function loadXMLDoc(dname,type){
	//get the proper xml object (based on browser of user)
	xmlhttp = GetXMLHTTPObject();
 
	//if no object was found, tell the user that their browser is not supported
	if (xmlhttp==null){
	  alert ("Your browser is not supported!");
	  return; //break the current function loadXMLDoc
  	}
 
	//keep track of the state
	xmlhttp.onreadystatechange = function(){
		//finishing state
		if (xmlhttp.readyState==4){
			//successful codes: 200 for webserver and 0 for local
			if (xmlhttp.status == 200 || xmlhttp.status == 0){
				//process code here
				if(type == "contact-cards")
					createContactCards(xmlhttp.responseXML); //located at contactcards.js
				if(type == "contact-profile")
					createProfile(xmlhttp.responseXML); //located at profiles.js
			}
			//let the user know that there was an error loading the xml document
			else{
				//should handle the error better
				alert("Error Loading XML");
			}
		}	
	}
	//get the document and keep track of what is happening in a queue by setting asynch to true
	xmlhttp.open("GET",dname,true);
	xmlhttp.send("");
}
 
//get the proper xml object
function GetXMLHTTPObject(){
	if (window.XMLHttpRequest){ // for all browsers besides ie 5 and 6 and perhaps 7
		return new XMLHttpRequest();
	}else if (window.ActiveXObject){ // catch ie 5/6/7
		return new ActiveXObject("Microsoft.XMLHTTP");
	}
	return null;
}
//END OF XML LOADING