无法显示网页

Question

当用户点击菜单栏中的链接时，我使用XMLHttpRequest来获取页面内容。

当我点击菜单栏中的任何链接时，它会抛出错误。页面也是打开的，但内容不会停留一段时间。加载页面后会自动消失。

  

[Deprecation]主线程上的同步XMLHttpRequest因其对最终用户体验的不利影响而被弃用。如需更多帮助，请查看https://xhr.spec.whatwg.org/。

function loadFile (id, fileURL){
	// get the element in HTML page
	var ele = document.getElementById (id);
	if (!ele){
		alert ("no id found to fill data!");
		return;
	}
	populateData (ele, fileURL);
}

// stream data of file "fileURL" into HTML element "ele"
function populateData (ele, fileURL){
	var req = false;
	if (window.XMLHttpRequest){
		try{
			req = new XMLHttpRequest ();
		}catch(E){
			req = false;
		}
	}else if (window.ActiveXObject){
		try{
			req = new ActiveXObject ("Msxml2.XMLHTTP");
		}catch(E){
			try{
				req = new ActiveXObject ("Microsoft.XMLHTTP");
			}catch(E){
				req = false;
			}
		}
	}// end of if
	
	// open the page whose content will be populated in the element
	if (req){
		try{
			req.open('GET', fileURL, false);
		}catch(E){
			alert ("error reading file!");
		}
		req.send (null);
		ele.innerHTML = req.responseText;
	}else{
		ele.innerHTML = "Your browser doesn't support loading file."
	}
}