StreamWebSocket class

Applies to Windows and Windows Phone

Supports network communication that allows reading and writing streams using a WebSocket.

Syntax


public sealed class StreamWebSocket : IWebSocket,
    IDisposable

Attributes

[DualApiPartition()]
[MarshalingBehavior(Agile)]
[Threading(Both)]
[Version(0x06020000)]

Members

The StreamWebSocket class has these types of members:

Constructors

The StreamWebSocket class has these constructors.

ConstructorDescription
StreamWebSocket Creates a new StreamWebSocket object.

 

Events

The StreamWebSocket class has these events.

EventDescription
Closed Occurs when a close frame is received on the StreamWebSocket object as part of the close handshake.

 

Methods

The StreamWebSocket class has these methods. With C#, Visual Basic, and C++, it also inherits methods from the Object class.

MethodDescription
Close() [C++, JavaScript]Closes the StreamWebSocket and sends an empty close frame to the server.
Close(UInt16, String) Closes the StreamWebSocket and indicates a reason for the closure.
ConnectAsync Starts an asynchronous operation to connect to a remote network destination on a StreamWebSocket object.
Dispose [C#, VB]Performs tasks associated with freeing, releasing, or resetting unmanaged resources. The ControlChannelTrigger class is not supported on Windows Phone.
SetRequestHeader Adds an HTTP request header to the HTTP request message used in the WebSocket protocol handshake by the StreamWebSocket object.

 

Properties

The StreamWebSocket class has these properties.

PropertyAccess typeDescription

Control

Read-onlyGets socket control data on a StreamWebSocket object.

Information

Read-onlyGets socket information on a StreamWebSocket object.

InputStream

Read-onlyGets the input stream to read from the remote destination on a StreamWebSocket object.

OutputStream

Read-onlyGets the output stream to write to the remote network destination on a StreamWebSocket object.

 

Remarks

The StreamWebSocket class provides a stream-based abstraction of the message-based WebSocket protocol. This is useful for scenarios in which large files (such as photos or movies) need to be transferred. Using StreamWebSocket allows sections of a message to be read with each read operation, rather than requiring the entire message to be read in a single operation (as with MessageWebSocket).

StreamWebSocket only supports binary messages. For UTF-8 messages, MessageWebSocket must be used.

Handling exceptions

You must write code to handle exceptions when you call asynchronous methods on the StreamWebSocket class. Exceptions can result from parameter validation errors, name resolutions failures, and network errors. Exceptions from network errors (loss of connectivity, connection failures, and HTTP server failures, for example) can happen at any time. These errors result in exceptions being thrown. If not handled by your app, an exception can cause your entire app to be terminated by the runtime.

The Windows.Networking.Sockets namespace has a convenient helper method and enumeration for handling errors when using WebSockets. This can be useful for handling specific network exceptions differently in your app. An app can also use the HRESULT from the exception on parameter validation errors to learn more detailed information on the error that caused the exception.

For more information on possible exceptions and how to handle exceptions, see Handling exceptions in network apps.

Using StreamWebSocket on Windows Server 2012

On Windows Server 2012 and Windows Server 2012 R2, the Windows.Networking.dll that implements most of the classes in the Windows.Networking.Sockets namespace will fail to load unless the Media Foundation feature is enabled. As a result, apps that use StreamWebSocket and related WebSocket classes in the Windows.Networking.Sockets namespace will fail if the Media Foundation feature is disabled. Windows Server 2012 or Windows Server 2012 R2 installs with the Media Foundation feature disabled.

The Media Foundation feature can be enabled on Windows Server 2012 or Windows Server 2012 R2 using Server Manager or by entering the following text in a command prompt or a script:

dism /online /enable-feature /featurename:ServerMediaFoundation

After the Media Foundation feature is enabled, the user is prompted to restart. Once the computer is restarted, classes for sockets and WebSockets in the Windows.Networking.Sockets namespace will work as expected.

Requirements

Minimum supported client

Windows 8 [Windows Store apps, desktop apps]

Minimum supported server

Windows Server 2012 [Windows Store apps, desktop apps]

Minimum supported phone

Windows Phone 8.1 [Windows Runtime apps only]

Namespace

Windows.Networking.Sockets
Windows::Networking::Sockets [C++]

Metadata

Windows.winmd

DLL

Windows.Networking.dll

Capabilities

internetClient
privateNetworkClientServer

See also

Other
Connecting with WebSockets (HTML)
Connecting with WebSockets (XAML)
Handling exceptions in network apps
How to connect with a StreamWebSocket (HTML)
How to connect with a StreamWebSocket (XAML)
How to use advanced WebSocket controls (HTML)
How to use advanced WebSocket controls (XAML)
Reference
MessageWebSocket
StreamWebSocketControl
StreamWebSocketInformation
Samples
Connecting with WebSockets sample
ControlChannelTrigger StreamWebSocket sample

 

 

Show:
© 2014 Microsoft