Flex 取得浏览器hostname

Flash可以被嵌入其他的服务器网页中，如果要flash取得其嵌入的网页的整个URL地址或者hostname等，应该怎么办呢？

<?xml version="1.0" encoding="utf-8"?>
<s:Application xmlns:fx="http://ns.adobe.com/mxml/2009" 
			   xmlns:s="library://ns.adobe.com/flex/spark" 
			   xmlns:mx="library://ns.adobe.com/flex/mx" minWidth="955" minHeight="600" 
			   preinitialize="application1_preinitializeHandler(event)"
			   applicationComplete="application1_applicationCompleteHandler(event)">
	<fx:Script>
		<![CDATA[
			import mx.core.FlexGlobals;
			import mx.events.FlexEvent;
			
			protected function application1_applicationCompleteHandler(event:FlexEvent):void
			{
				trace("laoderInfo.url=" + loaderInfo.url);
				//如果要用loaderInfo去取得所加载的swf的url，则必须在applicationComplete完成后
				
			}
			
			protected function application1_preinitializeHandler(event:FlexEvent):void
			{
				trace("topLevelApplication.url=" + FlexGlobals.topLevelApplication.url);
				//在FlexGlobals.topLevelApplication.url中，则在preinitialize时候就可以取得了。
				trace("browser‘s url=" + ExternalInterface.call("eval", "window.location.url"));
				trace("browser‘s hostname=" + ExternalInterface.call("eval", "window.location.hostname"));
				//取得浏览器的url
			}
		]]>
	</fx:Script>
</s:Application>