拷贝文件，返回新文件路径及文件名，同名的不同文件加后缀（1）

        /// <summary>
        /// 拷贝文件，返回新文件路径及文件名，同名的不同文件加后缀（1）
        /// </summary>
        /// <param name="sourceFileName"></param>
        /// <param name="destFileName"></param>
        /// <returns></returns>
        private string GetCopyPathFileName(string sourceFileName, string destFileName)
        {
            string sourceFileMD5 = Encrypt.GetMD5HashFromFile(sourceFileName);

            string directory = Path.GetDirectoryName(destFileName);
            string filename = Path.GetFileNameWithoutExtension(destFileName);
            string extension = Path.GetExtension(destFileName);

            int counter = 1;

            string newFullPath = destFileName;

            while (System.IO.File.Exists(newFullPath) && Encrypt.GetMD5HashFromFile(newFullPath) != sourceFileMD5)
            {
                string newFilename = filename + "(" + counter + ")" + extension;
                newFullPath = Path.Combine(directory, newFilename);
                counter++;
            }

            if (!File.Exists(newFullPath))
            {
                File.Copy(sourceFileName, newFullPath);
            }
            return newFullPath;
        }