C#利用WebService接口下载文件

             WebTest.RtTfSimDataInterface test = new WebTest.RtTfSimDataInterface();
             //string strBasic = test.GetTfBasicDataInfo("admin", "123", "11", true);
             string strRealTime = test.GetTfRealTimeDataInfo("admin", "", "", true);
             //string strjson = HttpUtility.UrlDecode(HttpUtility.UrlEncode(str));

             WebTest.xsdDwgInfo dd = test.GetTfDwgBinaryInfo("admin", "admin", "", );

             /////////////////////////////////////////////////////////////////////////////
             int nReadSize = dd.mnReadSize;//读取文件大小
             sbyte[] mySByte = new sbyte[nReadSize];
             mySByte = dd.mpBuffer;
             bool bEof = dd.mbEof;
             string strFileName = dd.mstrFileName;//文件名称
             string strDwg_UpdateTime = dd.mstrDwgUpdateTime;//文件最后更新时间
             //写数据

             byte[] arr = new byte[nReadSize];
             Buffer.BlockCopy(mySByte, , arr, , nReadSize);//sbyte[]转byte[]

             if (!File.Exists("E:\\a.dwg"))
             {
                 FileStream FsCreate = new FileStream("E:\\a.dwg", FileMode.Create);
                 FsCreate.Close();
             }
             FileStream fs = new FileStream("E:\\a.dwg", FileMode.Append, FileAccess.Write);
             fs.Write(arr, , nReadSize);//写入byte[]
             fs.Close();

             int nPosition = dd.mnReadSize;//读取文件位置

             while (!bEof)//文件未下载完成，继续下载
             {
                 dd = test.GetTfDwgBinaryInfo("admin", "admin", "", nPosition);
                 nPosition += dd.mnReadSize;
                 bEof = dd.mbEof;
                 nReadSize = dd.mnReadSize;
                 sbyte[] sbyteTmp = new sbyte[nReadSize];
                 sbyteTmp = dd.mpBuffer;

                 byte[] arrTmp = new byte[sbyteTmp.Length];
                 Buffer.BlockCopy(sbyteTmp, , arrTmp, , sbyteTmp.Length);

                 if (!File.Exists("E:\\a.dwg"))
                 {
                     FileStream FsCreate = new FileStream("E:\\a.dwg", FileMode.Create);
                     FsCreate.Close();
                 } FileStream fsTmp = new FileStream("E:\\a.dwg", FileMode.Append, FileAccess.Write);
                 fsTmp.Write(arrTmp, , nReadSize);
                 fsTmp.Close();
             }