驗證 Youtube 影片是否存在

gistfile1.as

    // 驗證 Youtube *******************************************************************
    private function validateHaveVideoID(str:String):String
		{
			var pattern:RegExp = /(?<=v(\=|\/))([-a-zA-Z0-9_]+)|(?<=youtu\.be\/)([-a-zA-Z0-9_]+)/gm;
			var result:Object = pattern.exec(str);
			//trace(result);
			if (result) {
				return result[0];
			}else {
				return null;
			}
		}
		
		private function validateVideoExist(str:String):void
		{
			var url:String = "http://gdata.youtube.com/feeds/api/videos/" + str + "?v=2&alt=json";
			var _loader:DataLoader = new DataLoader(url, new DataLoaderVars().noCache(true).onError(onYoutubeError).onComplete(onYoutubeComplete).vars);
			_loader.load();
		}
		
		private function onYoutubeError(e:LoaderEvent):void 
		{
			var _loader:DataLoader = e.target as DataLoader;
			_loader.dispose(true);
			// 影片不存在
			JS.alert("你輸入的Youtube分享連結無效，請確認");
			
		}
		
		private function onYoutubeComplete(e:LoaderEvent):void 
		{
			var _loader:DataLoader = e.target as DataLoader;
			try {
				var data:Object = JSON.decode(_loader.content);
			}catch (err:Error) {
				trace("onYoutubeComplete | Error");
			}
			if (data.entry) {
				//t.obj(data);
				youtube_title = data.entry.title.$t;
				trace(youtube_title);
				// 影片存在
				
			}else {
				// 影片不存在
				JS.alert("你輸入的Youtube分享連結無效，請確認");
				
			}
			_loader.dispose(true);
		}