AWS SDK for .NET Documentation
InitiateMultipartUpload Method (request)
AmazonAmazon.S3AmazonS3InitiateMultipartUpload(InitiateMultipartUploadRequest) Did this page help you?   Yes   No    Tell us about it...
Initiates a multipart upload and returns an InitiateMultipartUploadResponse which contains an upload ID.
Declaration Syntax
Parameters
request (InitiateMultipartUploadRequest)
The InitiateMultipartUploadRequest that defines the parameters of the operation.
Return Value
Returns a InitiateMultipartUploadResponse from S3.
Remarks

The upload ID associates all the parts in the specific upload. You specify this upload ID in each of your subsequent Upload Part requests. You also include this upload ID in the final request to either complete, or abort the multipart upload request.

After you initiate a multipart upload and upload one or more parts, you must either complete or abort the multipart upload in order to stop getting charged for storage of the uploaded parts. Once you complete or abort the multipart upload, Amazon S3 will release the stored parts and stop charging you for their storage.

Examples

This example shows how to upload 13MB of data using mutlipart upload.
The data is contained in a stream and the upload is done in 3 parts: 5MB, 5MB, then the remainder.

CopyMultipart Upload Sample
int MB = (int)Math.Pow(2, 20);

// Create a client
AmazonS3Client client = new AmazonS3Client();

// Define input stream
Stream inputStream = Create13MBDataStream();

// Initiate multipart upload
InitiateMultipartUploadRequest initRequest = new InitiateMultipartUploadRequest
{
    BucketName = "SampleBucket",
    Key = "Item1"
};
InitiateMultipartUploadResponse initResponse = client.InitiateMultipartUpload(initRequest);

// Upload part 1
UploadPartRequest uploadRequest = new UploadPartRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartNumber = 1,
    PartSize = 5 * MB,
    InputStream = inputStream
};
UploadPartResponse up1Response = client.UploadPart(uploadRequest);

// Upload part 2
uploadRequest = new UploadPartRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartNumber = 2,
    PartSize = 5 * MB,
    InputStream = inputStream
};
UploadPartResponse up2Response = client.UploadPart(uploadRequest);

// Upload part 3
uploadRequest = new UploadPartRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartNumber = 3,
    InputStream = inputStream
};
UploadPartResponse up3Response = client.UploadPart(uploadRequest);

// List parts for current upload
ListPartsRequest listPartRequest = new ListPartsRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId
};
ListPartsResponse listPartResponse = client.ListParts(listPartRequest);
Debug.Assert(listPartResponse.Parts.Count == 3);

// Complete the multipart upload
CompleteMultipartUploadRequest compRequest = new CompleteMultipartUploadRequest
{
    BucketName = "SampleBucket",
    Key = "Item1",
    UploadId = initResponse.UploadId,
    PartETags = new List<PartETag>
    {
        new PartETag { ETag = up1Response.ETag, PartNumber = 1 },
        new PartETag { ETag = up2Response.ETag, PartNumber = 2 },
        new PartETag { ETag = up3Response.ETag, PartNumber = 3 }
    }
};
CompleteMultipartUploadResponse compResponse = client.CompleteMultipartUpload(compRequest);

Assembly: AWSSDK (Module: AWSSDK) Version: 1.5.60.0 (1.5.60.0)