Initiates an asynchronous operation to open a stream for writing to the blob.
Assembly: Microsoft.WindowsAzure.Storage (in Microsoft.WindowsAzure.Storage.dll)
Syntax
[DoesServiceRequestAttribute] public virtual Task<CloudBlobStream> OpenWriteAsync( bool createNew, AccessCondition accessCondition, BlobRequestOptions options, OperationContext operationContext, CancellationToken cancellationToken )
public: [DoesServiceRequestAttribute] virtual Task<CloudBlobStream^>^ OpenWriteAsync( bool createNew, AccessCondition^ accessCondition, BlobRequestOptions^ options, OperationContext^ operationContext, CancellationToken cancellationToken )
[<DoesServiceRequestAttribute>] abstract OpenWriteAsync : createNew:bool * accessCondition:AccessCondition * options:BlobRequestOptions * operationContext:OperationContext * cancellationToken:CancellationToken -> Task<CloudBlobStream> [<DoesServiceRequestAttribute>] override OpenWriteAsync : createNew:bool * accessCondition:AccessCondition * options:BlobRequestOptions * operationContext:OperationContext * cancellationToken:CancellationToken -> Task<CloudBlobStream>
<DoesServiceRequestAttribute> Public Overridable Function OpenWriteAsync ( createNew As Boolean, accessCondition As AccessCondition, options As BlobRequestOptions, operationContext As OperationContext, cancellationToken As CancellationToken ) As Task(Of CloudBlobStream)
Parameters
- createNew
-
Type:
System.BooleanSystem::BooleanSystem.BooleanSystem.Boolean
Use true to create a new append blob or overwrite an existing one, false to append to an existing blob.
- accessCondition
-
Type:
Microsoft.WindowsAzure.Storage.AccessConditionMicrosoft.WindowsAzure.Storage::AccessCondition^Microsoft.WindowsAzure.Storage.AccessConditionMicrosoft.WindowsAzure.Storage.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
-
Type:
Microsoft.WindowsAzure.Storage.Blob.BlobRequestOptionsMicrosoft.WindowsAzure.Storage.Blob::BlobRequestOptions^Microsoft.WindowsAzure.Storage.Blob.BlobRequestOptionsMicrosoft.WindowsAzure.Storage.Blob.BlobRequestOptions
A BlobRequestOptions object that specifies additional options for the request.
- operationContext
-
Type:
Microsoft.WindowsAzure.Storage.OperationContextMicrosoft.WindowsAzure.Storage::OperationContext^Microsoft.WindowsAzure.Storage.OperationContextMicrosoft.WindowsAzure.Storage.OperationContext
An OperationContext object that represents the context for the current operation.
- cancellationToken
-
Type:
System.Threading.CancellationTokenSystem.Threading::CancellationTokenSystem.Threading.CancellationTokenSystem.Threading.CancellationToken
A CancellationToken to observe while waiting for a task to complete.
Return Value
Type: System.Threading.Tasks.Task<CloudBlobStream>System.Threading.Tasks::Task<CloudBlobStream^>^System.Threading.Tasks.Task<CloudBlobStream>System.Threading.Tasks.Task(Of CloudBlobStream)A Task<TResult><TResult><'TResult>(Of TResult) object of type CloudBlobStream that represents the asynchronous operation.
Remarks
Note that this method always makes a call to the FetchAttributesAsync method under the covers. Set the StreamWriteSizeInBytesStreamWriteSizeInBytesStreamWriteSizeInBytesStreamWriteSizeInBytes property before calling this method to specify the block size to write, in bytes, ranging from between 16 KB and 4 MB inclusive. If you have a single-writer scenario, see AbsorbConditionalErrorsOnRetryAbsorbConditionalErrorsOnRetryAbsorbConditionalErrorsOnRetryAbsorbConditionalErrorsOnRetry to determine whether setting this flag to true is acceptable for your scenario.