/* *url-loading object and a request queue built on top of it *//* namespacing object */var Darkness = new Object();Darkness.READY_STATE_UNINITIALIZED=0;Darkness.READY_STATE_LOADING=1;Darkness.READY_STATE_LOADED=2;Darkness.READY_STATE_INTERACTIVE=3;Darkness.READY_STATE_COMPLETE=4;/*--- content loader object for cross-browser requests ---*/Darkness.ContentLoader = function(url,onload,onerror,method,params,contentType){  //this.url = url;  this.req=null;  this.onload = onload;  this.onerror=(onerror) ? onerror : this.defaultError;  this.loadXMLDoc(url,method,params,contentType);}Darkness.ContentLoader.prototype = {	initXMLHTTPRequest:function(){		if (window.XMLHttpRequest) {        return new XMLHttpRequest();    } else if (window.ActiveXObject) {        return new ActiveXObject("Microsoft.XMLHTTP");    }    return null;	},	onReadyState: function(){	  var req = this.req;	  var ready = req.readyState;	  	  if (ready == Darkness.READY_STATE_COMPLETE){	  	var httpStatus = req.status;	    if (httpStatus==200 || httpStatus==0){	      this.onload.call(this);	    }else{	      this.onerror.call(this);	    }	  }	},	loadXMLDoc: function(url,method,params,contentType){	  method = method ||"GET";	  	  if (!contentType && method=="POST"){	    contentType='application/x-www-form-urlencoded';	  }	  this.req = this.initXMLHTTPRequest();	  if (this.req){	    try{	      var loader = this;	      this.req.onreadystatechange = function(){	        loader.onReadyState.call(loader);	      }	      this.req.open(method,url,true);	      if (contentType){	        this.req.setRequestHeader('Content-Type', contentType);	      }	      this.req.send(params);	    }catch (err){	      this.onerror.call(this);	    }	  }	},	defaultError:function(){	  alert("error fetching data!"	    +"\n\nreadyState:"+this.req.readyState	    +"\nstatus: "+this.req.status	    +"\nheaders: "+this.req.getAllResponseHeaders());	}}