Export (0) Print
Expand All

WebClient.OpenWriteAsync Method (Uri)

Opens a stream for writing data to the specified resource. This method does not block the calling thread.

Namespace:  System.Net
Assembly:  System (in System.dll)

[HostProtectionAttribute(SecurityAction.LinkDemand, ExternalThreading = true)]
public void OpenWriteAsync(
	Uri address
)

Parameters

address
Type: System.Uri
The URI of the resource to receive the data.

ExceptionCondition
ArgumentNullException

The address parameter is null.

This method retrieves a writable stream that is used to send data to a resource. The stream is retrieved using thread resources that are automatically allocated from the thread pool. To receive notification when the stream is available, add an event handler to the OpenWriteCompleted event. When you close the stream, the thread blocks until the request is sent to address and a response is received.

This method does not block the calling thread while the stream is being opened. To block while waiting for the stream, use one of the OpenWrite methods.

If the BaseAddress property is not an empty string ("") and address does not contain an absolute URI, address must be a relative URI that is combined with BaseAddress to form the absolute URI of the requested data. If the QueryString property is not an empty string, it is appended to address.

This method uses the STOR command to upload an FTP resource. For an HTTP resource, the POST method is used.

NoteNote

This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing.

NoteNote

The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: ExternalThreading. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

Community Additions

ADD
Show:
© 2014 Microsoft