/// <summary>
        /// 写入
        /// </summary>
        /// <param name="value">值</param>
        /// <param name="useLf">是否换行</param>
        private void Write(byte[] value, bool useLf)
        {
            if (value == null)
            {
                return;
            }
            if (useLf)
            {
                value.AddLf();
            }
            var list = new List <byte>();

            if (_buffer != null)
            {
                list.AddRange(_buffer);
            }
            list.AddRange(value);
            _buffer = list.ToArray();
        }