Use Dojo to Replace PrototypeJS codes

1.Old PrototypeJS Script:

var loc = document.location.pathname;
var tail = "webengine/generated/Init"
loc = loc.substr(0,loc.indexOf(tail));
var url = loc.concat("protect/RouterServlet?NAV_MENU=TRUE&GREEN_NAV=TRUE");
				
new Ajax.Request(url,{method:'get',onSuccess:function(request){
var elemAjxResp = request.responseText;
document.getElementById('com-navigation').innerHTML = elemAjxResp;;
}});

2. Use Dojo Ajax and dom operation;

require(["dojo/_base/xhr","dojo/dom","dojo/domready!"],function(xhr,dom) {        
        xhr.get({            
            url: url,load: function(newContent) {
                dom.byId("com-navigation").innerHTML = newContent;
            },error: function() {
			
            }
        });         
});