public override void Close()
    {
        _sink.Close();
    }

    public override void Flush()
    {
        _sink.Flush();
    }

    public override int Read(byte[] buffer, int offset, int count)
    {
        return _sink.Read(buffer, offset, count);
    }

    // The Write method actually does the filtering.
    public override void Write(byte[] buffer, int offset, int count)
    {
        string szBuffer = System.Text.UTF8Encoding.UTF8.GetString(buffer, offset, count);
        string ap = "action=\"";
        int pos = -1;
        if ((pos = szBuffer.IndexOf(ap)) != -1)
        {
            int epos = szBuffer.IndexOf("\"", pos + ap.Length + 1);
            if (epos != -1)
            {
                szBuffer = szBuffer.Remove(pos + ap.Length, epos - pos - ap.Length);
            }
            szBuffer = szBuffer.Insert(pos + ap.Length, this.str);

            byte[] data = System.Text.UTF8Encoding.UTF8.GetBytes(szBuffer);
            _sink.Write(data, 0, data.Length);
        }
        else
        {
            oOutput.Append(szBuffer);
        }
        //下面的这一段可以用来修改之间的内容；
        //Regex oEndFile = new Regex("", RegexOptions.IgnoreCase|RegexOptions.Compiled);
        //if (oEndFile.IsMatch(szBuffer))
        //{
        // //Append the last buffer of data
        // //附加上缓冲区中的最后一部分数据
        // oOutput.Append(szBuffer);
        // //Get back the complete response for the client
        // //传回完整的客户端返回数据
        // string szCompleteBuffer = oOutput.ToString().ToLower();
        // int ipos = szCompleteBuffer.IndexOf("",ipos+7);
        // string sp = szCompleteBuffer.Substring(ipos+7, epos - ipos );
        // szCompleteBuffer = szCompleteBuffer.Remove(ipos+7,sp.Length-7);
        // szCompleteBuffer = szCompleteBuffer.Insert(ipos + 7, "dhz");
        // // szCompleteBuffer = szCompleteBuffer.Replace(sp, "dhz");
        // //No match, so write out original data
        // //没有匹配，因此写入源代码
        // byte[] data = System.Text.UTF8Encoding.UTF8.GetBytes(szCompleteBuffer);
        // _sink.Write(data, 0, data.Length);
        //}
        //else
        //{
        // oOutput.Append(szBuffer);
        //}
    }
}