C#从Google云端硬盘下载电子表格

时间:2015-12-03 09:05:25

标签: c# google-drive-api google-api-dotnet-client

我尝试使用FileResource API中的ExportLinks从Google云端硬盘下载工作表。

但是,我得到的回复不是电子表格,而是代表电子表格的HTML文件或类似内容。

以下是我使用的请求:

            FilesResource.GetRequest getF = new FilesResource.GetRequest(service, "1y92Rok6oYKMwvc-Oq4Uurah7y552sfmIbyD9Wzmpq54");
            Google.Apis.Drive.v2.Data.File f = getF.Execute();
            string downloadUrl = f.ExportLinks["application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"];
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(new Uri(downloadUrl));
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            ReadWriteStream(response.GetResponseStream(), File.OpenWrite("D:\\tmp.xlsx"));

我用来存储流的功能:

static private void ReadWriteStream(Stream readStream, Stream writeStream)
        {
            int Length = 256;
            Byte[] buffer = new Byte[Length];
            int bytesRead = readStream.Read(buffer, 0, Length);
            // write the required bytes
            while (bytesRead > 0)
            {
                writeStream.Write(buffer, 0, bytesRead);
                bytesRead = readStream.Read(buffer, 0, Length);
            }
            readStream.Close();
            writeStream.Close();
        }

有谁可以指出我做错了什么?

1 个答案:

答案 0 :(得分:2)

这是我通常使用的方法

/// <summary>
        /// Download a file
        /// Documentation: https://developers.google.com/drive/v2/reference/files/get
        /// </summary>
        /// <param name="_service">a Valid authenticated DriveService</param>
        /// <param name="_fileResource">File resource of the file to download</param>
        /// <param name="_saveTo">location of where to save the file including the file name to save it as.</param>
        /// <returns></returns>
        public static Boolean downloadFile(DriveService _service, File _fileResource, string _saveTo)
        {

            if (!String.IsNullOrEmpty(_fileResource.DownloadUrl))
            {
                try
                {
                    var x = _service.HttpClient.GetByteArrayAsync(_fileResource.DownloadUrl );
                    byte[] arrBytes = x.Result;
                    System.IO.File.WriteAllBytes(_saveTo, arrBytes);
                    return true;                  
                }
                catch (Exception e)
                {
                    Console.WriteLine("An error occurred: " + e.Message);
                    return false;
                }
            }
            else
            {
                // The file doesn't have any content stored on Drive.
                return false;
            }
        }