CloudPageBlob.OpenWrite Method

Definition

Opens a stream for writing to the blob. If the blob already exists, then existing data in the blob may be overwritten.

[Microsoft.Azure.Storage.DoesServiceRequest]
public virtual Microsoft.Azure.Storage.Blob.CloudBlobStream OpenWrite (long? size, Microsoft.Azure.Storage.AccessCondition accessCondition = default, Microsoft.Azure.Storage.Blob.BlobRequestOptions options = default, Microsoft.Azure.Storage.OperationContext operationContext = default);
[<Microsoft.Azure.Storage.DoesServiceRequest>]
abstract member OpenWrite : Nullable<int64> * Microsoft.Azure.Storage.AccessCondition * Microsoft.Azure.Storage.Blob.BlobRequestOptions * Microsoft.Azure.Storage.OperationContext -> Microsoft.Azure.Storage.Blob.CloudBlobStream
override this.OpenWrite : Nullable<int64> * Microsoft.Azure.Storage.AccessCondition * Microsoft.Azure.Storage.Blob.BlobRequestOptions * Microsoft.Azure.Storage.OperationContext -> Microsoft.Azure.Storage.Blob.CloudBlobStream
Public Overridable Function OpenWrite (size As Nullable(Of Long), Optional accessCondition As AccessCondition = Nothing, Optional options As BlobRequestOptions = Nothing, Optional operationContext As OperationContext = Nothing) As CloudBlobStream

Parameters

size
Nullable<Int64>

The size of the page blob, in bytes. The size must be a multiple of 512. If null, the page blob must already exist.

accessCondition
AccessCondition

An AccessCondition object that represents the condition that must be met in order for the request to proceed. If null, no condition is used.

options
BlobRequestOptions

A BlobRequestOptions object that specifies additional options for the request. If null, default options are applied to the request.

operationContext
OperationContext

An OperationContext object that represents the context for the current operation.

Returns

A CloudBlobStream object.

Attributes

Remarks

Note that this method always makes a call to the FetchAttributes(AccessCondition, BlobRequestOptions, OperationContext) method under the covers.

Set the StreamWriteSizeInBytes property before calling this method to specify the block size to write, in bytes, ranging from between 16 KB and 4 MB inclusive.

To throw an exception if the blob exists instead of overwriting it, pass in an AccessCondition object generated using GenerateIfNotExistsCondition().

Applies to