Socket.EndSend Method
Definition
Important
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Ends a pending asynchronous send.
Overloads
| EndSend(IAsyncResult) |
Ends a pending asynchronous send. |
| EndSend(IAsyncResult, SocketError) |
Ends a pending asynchronous send. |
EndSend(IAsyncResult)
Ends a pending asynchronous send.
public:
int EndSend(IAsyncResult ^ asyncResult);
public:
int EndSend(IAsyncResult ^ result);
public int EndSend (IAsyncResult asyncResult);
public int EndSend (IAsyncResult result);
member this.EndSend : IAsyncResult -> int
member this.EndSend : IAsyncResult -> int
Public Function EndSend (asyncResult As IAsyncResult) As Integer
Public Function EndSend (result As IAsyncResult) As Integer
Parameters
- asyncResultresult
- IAsyncResult
An IAsyncResult that stores state information for this asynchronous operation.
Returns
If successful, the number of bytes sent to the Socket; otherwise, an invalid Socket error.
Exceptions
asyncResult is null.
asyncResult was not returned by a call to the BeginSend(Byte[], Int32, Int32, SocketFlags, AsyncCallback, Object) method.
EndSend(IAsyncResult) was previously called for the asynchronous send.
An error occurred when attempting to access the socket.
The Socket has been closed.
Examples
The following code example ends a pending asynchronous send.
StateObject^ so = safe_cast<StateObject^>(ar->AsyncState);
Socket^ s = so->workSocket;
int send = s->EndSend( ar );
Console::WriteLine( "The size of the message sent was : {0}", send );
s->Close();
StateObject so = (StateObject) ar.AsyncState;
Socket s = so.workSocket;
int send = s.EndSend(ar);
Console.WriteLine("The size of the message sent was :" + send.ToString());
s.Close();
Public Shared Sub Send_Callback(ar As IAsyncResult)
Dim so As StateObject = CType(ar.AsyncState, StateObject)
Dim s As Socket = so.workSocket
Dim send As Integer = s.EndSend(ar)
Console.WriteLine(("The size of the message sent was :" + send.ToString()))
s.Close()
End Sub
Remarks
EndSend completes the asynchronous send operation started in BeginSend.
Before calling BeginSend, you need to create a callback method that implements the AsyncCallback delegate. This callback method executes in a separate thread and is called by the system after BeginSend returns. The callback method must accept the IAsyncResult returned by the BeginSend method as a parameter.
Within the callback method, call the AsyncState method of the IAsyncResult parameter to obtain the sending Socket. After obtaining the Socket, you can call the EndSend method to successfully complete the send operation and return the number of bytes sent.
If you are using a connectionless protocol, EndSend will block until the datagram is sent. If you are using a connection-oriented protocol, EndSend will block until some of the buffer was sent. If the return value from EndSend indicates that the buffer was not completely sent, call the BeginSend method again, modifying the buffer to hold the unsent data.
There is no guarantee that the data you send will appear on the network immediately. To increase network efficiency, the underlying system may delay transmission until a significant amount of outgoing data is collected. A successful completion of the BeginSend method means that the underlying system has had room to buffer your data for a network send.
Note
If you receive a SocketException, use the SocketException.ErrorCode property to obtain the specific error code. After you have obtained this code, refer to the Windows Sockets version 2 API error code documentation for a detailed description of the error.
Note
All I/O initiated by a given thread is canceled when that thread exits. A pending asynchronous operation can fail if the thread exits before the operation completes.
Note
The successful completion of a send does not indicate that the data was successfully delivered. If no buffer space is available within the transport system to hold the data to be transmitted, send will block unless the socket has been placed in nonblocking mode.
Note
This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing in the .NET Framework.
See also
- BeginSend(Byte[], Int32, Int32, SocketFlags, AsyncCallback, Object)
- AsyncCallback
- AsyncState
- SetSocketOption(SocketOptionLevel, SocketOptionName, Int32)
- NoDelay
Applies to
EndSend(IAsyncResult, SocketError)
Ends a pending asynchronous send.
public:
int EndSend(IAsyncResult ^ asyncResult, [Runtime::InteropServices::Out] System::Net::Sockets::SocketError % errorCode);
public int EndSend (IAsyncResult asyncResult, out System.Net.Sockets.SocketError errorCode);
member this.EndSend : IAsyncResult * SocketError -> int
Public Function EndSend (asyncResult As IAsyncResult, ByRef errorCode As SocketError) As Integer
Parameters
- asyncResult
- IAsyncResult
An IAsyncResult that stores state information for this asynchronous operation.
- errorCode
- SocketError
A SocketError object that stores the socket error.
Returns
If successful, the number of bytes sent to the Socket; otherwise, an invalid Socket error.
Exceptions
asyncResult is null.
asyncResult was not returned by a call to the BeginSend(Byte[], Int32, Int32, SocketFlags, AsyncCallback, Object) method.
EndSend(IAsyncResult) was previously called for the asynchronous send.
An error occurred when attempting to access the socket.
The Socket has been closed.
Remarks
EndSend completes the asynchronous send operation started in BeginSend.
Before calling BeginSend, you need to create a callback method that implements the AsyncCallback delegate. This callback method executes in a separate thread and is called by the system after BeginSend returns. The callback method must accept the IAsyncResult returned by the BeginSend method as a parameter.
Within the callback method, call the AsyncState method of the IAsyncResult parameter to obtain the sending Socket. After obtaining the Socket, you can call the EndSend method to successfully complete the send operation and return the number of bytes sent.
If you are using a connectionless protocol, EndSend will block until the datagram is sent. If you are using a connection-oriented protocol, EndSend will block until some of the buffer was sent. If the return value from EndSend indicates that the buffer was not completely sent, call the BeginSend method again, modifying the buffer to hold the unsent data.
There is no guarantee that the data you send will appear on the network immediately. To increase network efficiency, the underlying system may delay transmission until a significant amount of outgoing data is collected. A successful completion of the BeginSend method means that the underlying system has had room to buffer your data for a network send.
Note
If you receive a SocketException, use the SocketException.ErrorCode property to obtain the specific error code. After you have obtained this code, refer to the Windows Sockets version 2 API error code documentation for a detailed description of the error.
Note
All I/O initiated by a given thread is canceled when that thread exits. A pending asynchronous operation can fail if the thread exits before the operation completes.
Note
The successful completion of a send does not indicate that the data was successfully delivered. If no buffer space is available within the transport system to hold the data to be transmitted, send will block unless the socket has been placed in nonblocking mode.
Note
This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing in the .NET Framework.
See also
- BeginSend(Byte[], Int32, Int32, SocketFlags, AsyncCallback, Object)
- AsyncCallback
- AsyncState
- SetSocketOption(SocketOptionLevel, SocketOptionName, Int32)
- NoDelay