tencent cloud

using COSXML.Model.Object;
using COSXML.Auth;
using COSXML.Transfer;
using System;
using COSXML;
using System.Threading.Tasks;

namespace COSSnippet
{
    public class TransferDownloadObjectModel {

      private CosXml cosXml;

      TransferDownloadObjectModel() {
        CosXmlConfig config = new CosXmlConfig.Builder()
          .SetRegion("COS_REGION") // Set the default region. For abbreviations of COS regions, visit https://www.tencentcloud.com/document/product/436/6224?from_cn_redirect=1.
          .Build();

        string secretId = "SECRET_ID";   // SecretId of the TencentCloud API. For more information about how to obtain the API key, see https://console.tencentcloud.com/cam/capi.
        string secretKey = "SECRET_KEY"; // SecretKey of the TencentCloud API. For more information about how to obtain the API key, see https://console.tencentcloud.com/cam/capi.
        long durationSecond = 600;          // Validity period of the request signature in seconds
        QCloudCredentialProvider qCloudCredentialProvider = new DefaultQCloudCredentialProvider(secretId, 
          secretKey, durationSecond);

        this.cosXml = new CosXmlServer(config, qCloudCredentialProvider);
      }

      /// Download an object via advanced API
      public async Task TransferDownloadObject()
      {
        // Initialize TransferConfig
        TransferConfig transferConfig = new TransferConfig();
        // Manually set the part threshold for advanced APIs to 20 MB (default), which is supported from v5.4.26
        //transferConfig.DivisionForDownload = 20 * 1024 * 1024;
        // Manually set the part size of advanced APIs to 10 MB (default: 5 MB). We recommend you not set the size to a very small value because this may result in frequent retries or unacceptable download speeds.
        //transferConfig.SliceSizeForDownload = 10 * 1024 * 1024;

        // Initialize TransferManager
        TransferManager transferManager = new TransferManager(cosXml, transferConfig);

        String bucket = "examplebucket-1250000000"; // Bucket name in the format of BucketName-APPID
        String cosPath = "exampleobject"; // Location identifier of the object in the bucket, i.e., the object key
        string localDir = System.IO.Path.GetTempPath();// Local file directory
        string localFileName = "my-local-temp-file"; // Filename of the local file

        // Download an object
        COSXMLDownloadTask downloadTask = new COSXMLDownloadTask(bucket, cosPath, 
          localDir, localFileName);

        // Manually set maximum tasks (default: 5) for advanced APIs, which is supported from v5.4.26
        //downloadTask.SetMaxTasks(10);
        downloadTask.progressCallback = delegate (long completed, long total)
        {
            Console.WriteLine(String.Format("progress = {0:##.##}%", completed * 100.0 / total));
        };

        try {
          COSXML.Transfer.COSXMLDownloadTask.DownloadTaskResult result = await 
            transferManager.DownloadAsync(downloadTask);
          Console.WriteLine(result.GetResultInfo());
          string eTag = result.eTag;
        }
        catch (COSXML.CosException.CosClientException clientEx)
        {
          // Request failed
          Console.WriteLine("CosClientException: " + clientEx);
        }
        catch (COSXML.CosException.CosServerException serverEx)
        {
          // Request failed
          Console.WriteLine("CosServerException: " + serverEx.GetInfo());
        }
      }


      static void Main(string[] args)
      {
        TransferDownloadObjectModel m = new TransferDownloadObjectModel();

        /// Download an object via advanced API
        m.TransferDownloadObject().Wait();
      }
    }
}