根據基本目錄及文件的全路逕，創建相應的子目錄，爲保存文件作準備

        public static string GenerateDirectoryByFileFullPath(string basePath, string fileFullPath){

            DirectoryInfo dirInfo = new DirectoryInfo(basePath);

            string fileName = new DirectoryInfo(fileFullPath).Name;

            string subDir = fileFullPath.Replace(basePath, "").Replace(fileName, "").Trim('\\');

            return dirInfo.CreateSubdirectory(subDir).FullName;

        }