如何断开FileSink与独立存储文件的链接
用FileSink录制视频, 录制结束后调用
// 清空 FileSink 的相关联信息
_fileSink.CaptureSource = null;
_fileSink.IsolatedStorageFileName = null;
IsolatedStorageFile file = IsolatedStorageFile.GetUserStoreForApplication();
if (file.FileExists(videopath))
file.DeleteFile(videopath);