UdpAnySourceMulticastClient.BeginSendToGroup Method (Byte[], Int32, Int32, AsyncCallback, Object)

.NET Framework (current version)

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Note: This API is now obsolete.

Begins the operation of sending a packet to a joined multicast group and invokes the specified callback when a packet has been sent to the group.

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

[ObsoleteAttribute("This API supports the .NET Framework infrastructure and is not intended to be used directly from your code.", 
public IAsyncResult BeginSendToGroup(
	byte[] buffer,
	int offset,
	int count,
	AsyncCallback callback,
	object state


Type: System.Byte[]

The buffer that contains the data to send.

Type: System.Int32

The offset, in bytes, from the beginning of the buffer to read the data to be sent.

Type: System.Int32

The number of bytes to send from the buffer.

Type: System.AsyncCallback

The callback method to invoke when the operation completes.

Type: System.Object

Optional state information to pass to the callback method for this operation.

Return Value

Type: System.IAsyncResult

Returns IAsyncResult.

An IAsyncResult that references this operation.

Exception Condition

buffer is a null reference (Nothing in Visual Basic).


offset is less than 0


offset is greater than the length of the buffer.


count is less than 0


offset plus the count is greater than the length of the buffer.


The multicast group has not yet been joined.


The UdpAnySourceMulticastClient has been disposed.


An error occurred when attempting to access the socket. See the Remarks section for more information.

The BeginSendToGroup method begins an operation of sending a UDP packet to the joined multicast group.

The client must have completed a join to the multicast group.

The method specified in the callback parameter is invoked when a packet has received.

It is possible to have a socket failure if a receive operation fails synchronously, although this is uncommon with UDP. If a socket failure occurs, a SocketException is thrown. The error received is specified as a member of the SocketError enumeration.

.NET Framework
Available since 4.5
Available since 4.0
Windows Phone Silverlight
Available since 7.1
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