C#, S3 API

26 May 2021 S3 API Tutorials

C# S3 Examples

Creating a Connection

This creates a connection so that you can interact with the server.

using System;
using Amazon;
using Amazon.S3;
using Amazon.S3.Model;
string accessKey = "put your access key here!";
string secretKey = "put your secret key here!";
AmazonS3Config config = new AmazonS3Config();
config.ServiceURL = "objects.s3.z1storage.com";
AmazonS3Client s3Client = new AmazonS3Client(
 accessKey,
 secretKey,
 config
 );

Listing Owned Buckets

This gets a list of Buckets that you own. This also prints out the bucket name and creation date of each bucket.

ListBucketsResponse response = client.ListBuckets();
foreach (S3Bucket b in response.Buckets)
{
 Console.WriteLine("{0}t{1}", b.BucketName, b.CreationDate);
}

The output will look something like this:

mahbuckat1 2011-04-21T18:05:39.000Z

mahbuckat2 2011-04-21T18:05:48.000Z

mahbuckat3 2011-04-21T18:07:18.000Z

Creating a Bucket

This creates a new bucket called my-new-bucket

PutBucketRequest request = new PutBucketRequest();
request.BucketName = "my-new-bucket";
client.PutBucket(request);

Listing a Bucket’s Content

This gets a list of objects in the bucket. This also prints out each object’s name, the file size, and last modified date.

ListObjectsRequest request = new ListObjectsRequest();
request.BucketName = "my-new-bucket";
ListObjectsResponse response = client.ListObjects(request);
foreach (S3Object o in response.S3Objects)
{
 Console.WriteLine("{0}t{1}t{2}", o.Key, o.Size, o.LastModified);
}

The output will look something like this:

myphoto1.jpg 251262 2011-08-08T21:35:48.000Z

myphoto2.jpg 262518 2011-08-08T21:38:01.000Z

Deleting a Bucket

Note

The Bucket must be empty! Otherwise it won’t work!

DeleteBucketRequest request = new DeleteBucketRequest();
request.BucketName = "my-new-bucket";
client.DeleteBucket(request);

Forced Delete for Non-empty Buckets

Attention

not available

Creating an Object

This creates a file hello.txt with the string "Hello World!"

PutObjectRequest request = new PutObjectRequest();
request.BucketName = "my-new-bucket";
request.Key = "hello.txt";
request.ContentType = "text/plain";
request.ContentBody = "Hello World!";
client.PutObject(request);

Change an Object’s ACL

This makes the object hello.txt to be publicly readable, and secret_plans.txt to be private.

PutACLRequest request = new PutACLRequest();
request.BucketName = "my-new-bucket";
request.Key = "hello.txt";
request.CannedACL = S3CannedACL.PublicRead;
client.PutACL(request);
PutACLRequest request2 = new PutACLRequest();
request2.BucketName = "my-new-bucket";
request2.Key = "secret_plans.txt";
request2.CannedACL = S3CannedACL.Private;
client.PutACL(request2);

Download an Object (to a file)

This downloads the object perl_poetry.pdf and saves it in C:UserslarryDocuments

GetObjectRequest request = new GetObjectRequest();
request.BucketName = "my-new-bucket";
request.Key = "perl_poetry.pdf";
GetObjectResponse response = client.GetObject(request);
response.WriteResponseStreamToFile("C:UserslarryDocumentsperl_poetry.pdf");

Delete an Object

This deletes the object goodbye.txt

DeleteObjectRequest request = new DeleteObjectRequest();
request.BucketName = "my-new-bucket";
request.Key = "goodbye.txt";
client.DeleteObject(request);

Generate Object Download URLs (signed and unsigned)

This generates an unsigned download URL for hello.txt. This works because we made hello.txt public by setting the ACL above. This then generates a signed download URL for secret_plans.txt that will work for 1 hour. Signed download URLs will work for the time period even if the object is private (when the time period is up, the URL will stop working).

Note

The C# S3 Library does not have a method for generating unsigned URLs, so the following example only shows generating signed URLs.

GetPreSignedUrlRequest request = new GetPreSignedUrlRequest();
request.BucketName = "my-bucket-name";
request.Key = "secret_plans.txt";
request.Expires = DateTime.Now.AddHours(1);
request.Protocol = Protocol.HTTP;
string url = client.GetPreSignedURL(request);
Console.WriteLine(url);

The output of this will look something like:

http://objects.s3.z1storage.com/my-bucket-name/secret_plans.txt?Signature=XXXXXXXXXXXXXXXXXXXXXXXXXXX&Expires=1316027075&AWSAccessKeyId=XXXXXXXXXXXXXXXXXXX

Tags:
Share