Object Storage Service:Download a file to a local disk (C# SDK V2)

Permissions

By default, an Alibaba Cloud account has full permissions. RAM users and RAM roles have no permissions by default. Grant the required permissions through RAM Policy or Bucket Policy before running the sample code.

Download an object to a local file

The following example downloads an object from a bucket and saves it to a local file.

using OSS = AlibabaCloud.OSS.V2;  // Alias for the OSS SDK namespace.

// Required: set the region, bucket name, object key, and local file path.
var region   = "cn-hangzhou";
var bucket   = "<your-bucket-name>";
var key      = "<your-object-key>";      // Format: folder/objectName
var filePath = "<your-local-file-path>";

// Optional: override the default endpoint for the region.
var endpoint = null as string;
// Example: "https://oss-cn-hangzhou.aliyuncs.com"

// Load default SDK configuration and read credentials from environment variables
// (OSS_ACCESS_KEY_ID and OSS_ACCESS_KEY_SECRET).
var cfg = OSS.Configuration.LoadDefault();
cfg.CredentialsProvider = new OSS.Credentials.EnvironmentVariableCredentialsProvider();
cfg.Region = region;

if (endpoint != null)
{
    cfg.Endpoint = endpoint;
}

// Create the OSS client.
using var client = new OSS.Client(cfg);

// Stream the object directly to the local file path.
// This avoids loading the entire object into memory.
var result = await client.GetObjectToFileAsync(new OSS.Models.GetObjectRequest()
{
    Bucket = bucket,
    Key    = key,
}, filePath);

// Print the result.
Console.WriteLine("GetObjectToFile done");
Console.WriteLine($"StatusCode: {result.StatusCode}");
Console.WriteLine($"RequestId: {result.RequestId}");
Console.WriteLine("Response headers:");
result.Headers.ToList().ForEach(x => Console.WriteLine($"{x.Key}: {x.Value}"));

Replace the following placeholders before running the code:

References

For the complete sample, see GetObjectToFile.cs.