Check out example codes for "dynamodb s3 link". It will help you in understanding the concepts better.

Code Example 1

// Create a DynamoDBContext
var context = new DynamoDBContext();

// Create a book with an S3Link
Book myBook = new Book
{
	Id = 501,
	CoverImage = S3Link.Create(context, "myBucketName", "covers/AWSSDK.jpg", Amazon.RegionEndpoint.USWest2),
	Title = "AWS SDK for .NET Object Persistence Model Handling Arbitrary Data",
	ISBN = 999,
	BookAuthors = new List { "Jim", "Steve", "Pavel", "Norm", "Milind" }
};

// Save book to DynamoDB
context.Save(myBook);

// Use S3Link to upload the content to S3
myBook.CoverImage.UploadFrom("path/to/covers/AWSSDK.jpg");

// Get a pre-signed URL for the image
string coverURL = myBook.CoverImage.GetPreSignedURL(DateTime.Now.AddHours(5));

// Load book from DynamoDB
myBook = context.Load(501);

// Download file linked from S3Link
myBook.CoverImage.DownloadTo("path/to/save/cover/otherbook.jpg");

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