Socket.BeginSendTo(Byte[], Int

以异步方式将数据发送到特定远程主机stream socket sendto。Sends data asynchronously to a specific remote host.

public:
 IAsyncResult ^ BeginSendTo(cli::array <System::Byte> ^ buffer, int offset, int size, System::Net::Sockets::SocketFlags socket_flags, System::Net::EndPoint ^ remote_end, AsyncCallback ^ callback, System::Object ^ state);

public IAsyncResult BeginSendTo (byte[] buffer, int offset, int size, System.Net.Sockets.SocketFlags socket_flags, System.Net.EndPoint remote_end, AsyncCallback callback, object state);

member this.BeginSendTo : byte[] * int * int * System.Net.Sockets.SocketFlags * System.Net.EndPoint * AsyncCallback * obj -> IAsyncResult

Public Function BeginSendTo (buffer As Byte(), offset As Integer, size As Integer, socket_flags As SocketFlags, remote_end As EndPoint, callback As AsyncCallback, state As Object) As IAsyncResult

buffer

Byte 类型的数组，它包含要发送的数据。An array of type Byte that contains the data to send.

offset

buffer 中的从其开始发送数据的、从零开始编排的位置。The zero-based position in buffer at which to begin sending data.

要发送的字节数。The number of bytes to send.

socketFlags

SocketFlagsSocketFlagsSocketFlagsSocketFlags

SocketFlags 值的按位组合。A bitwise combination of the SocketFlags values.

remoteEP

EndPointEndPointEndPointEndPoint

表示远程设备的 EndPoint。An EndPoint that represents the remote device.

callback

AsyncCallbackAsyncCallbackAsyncCallbackAsyncCallback

AsyncCallback 委托。The AsyncCallback delegate.

state

一个对象，它包含此请求的状态信息。An object that contains state information for this request.

IAsyncResultIAsyncResultIAsyncResultIAsyncResult

引用异步发送的 IAsyncResult。An IAsyncResult that references the asynchronous send.

ArgumentNullExceptionArgumentNullExceptionArgumentNullExceptionArgumentNullException

buffer 为 null。buffer is null.

- 或 --or- remoteEP 为 nullstream socket sendto。remoteEP is null.

SocketExceptionSocketExceptionSocketExceptionSocketException

尝试访问套接字时出错。An error occurred when attempting to access the socket.

ArgumentOutOfRangeExceptionArgumentOutOfRangeExceptionArgumentOutOfRangeExceptionArgumentOutOfRangeException

offset 小于 0。offset is less than 0.

- 或 --or- offset 大于 buffer 的长度。offset is greater than the length of buffer.

- 或 --or- size 小于 0。size is less than 0.

- 或 --or- size 大于 buffer 的长度减去 offset 参数的值。size is greater than the length of buffer minus the value of the offset parameter.

ObjectDisposedExceptionObjectDisposedExceptionObjectDisposedExceptionObjectDisposedException

Socket 已关闭。The Socket has been closed.

SecurityExceptionSecurityExceptionSecurityExceptionSecurityException

调用堆栈中的较高调用方无权执行所请求的操作。A caller higher in the call stack does not have permission for the requested operation.

(我试运行了这段代码，如果通过数据绑定为datagridview添加数据，那么下面的代码将不会生效，因为它只能为非绑定方式添加的行排序，如果要以绑定方式添加数据，请参看我的示例程序)。所以send必须是异步发送.每次pop连接buffer中的数据,异步发送数据,成功后继续pop发送余下的数据,平时待发数据都push到连接buffer中,一但连接buffer数据超过一定大小,即可认定该连接已断线或者恶意不接受数据,直接kick(当然你也可以在send超时直接kick,但client可能只是偶尔延迟几秒，这样做势必导致玩家常常掉线.).。vb-get-webpage-source-demon.zip - 这是一个vb利用xmlhttp方式远程获取网页源码的示例，演示了post和get两种方法进行获取，可模拟提交表单数据进行远程登录，代码短小精悍，实用性很强。

IPHostEntry^ lipa = Dns::Resolve( "host.contoso.com" );
IPEndPoint^ lep = gcnew IPEndPoint( lipa->AddressList[ 0 ], 11000 );
Socket^ s = gcnew Socket( lep->Address->AddressFamily,
   SocketType::Stream,
   ProtocolType::Tcp );
try
{
   while ( true )
   {
      allDone->Reset();
      array<Byte>^ buff = Encoding::ASCII->GetBytes( "This is a test" );
      Console::WriteLine( "Sending Message Now.." );
      s->BeginSendTo( buff, 0, buff->Length, SocketFlags::None, lep,
         gcnew AsyncCallback( &Async_Send_Receive::Connect_Callback ), s );
      allDone->WaitOne();
   }
}
catch ( Exception^ e ) 
{
   Console::WriteLine( e );
}

IPHostEntry lipa = Dns.Resolve("host.contoso.com");
IPEndPoint lep = new IPEndPoint(lipa.AddressList[0], 11000);
      Socket s = new Socket(lep.Address.AddressFamily,
      	                           SocketType.Stream,
                                        ProtocolType.Tcp);
      try{
         
                while(true){
                allDone.Reset();
                byte[] buff = Encoding.ASCII.GetBytes("This is a test");
                
                Console.WriteLine("Sending Message Now..");
                s.BeginSendTo(buff, 0, buff.Length, 0, lep, new AsyncCallback(Async_Send_Receive.SendTo_Callback), s);
                allDone.WaitOne();
           }
      }
      catch (Exception e){
           Console.WriteLine(e.ToString());
      }

   Dim lipa As IPHostEntry = Dns.Resolve("host.contoso.com")
   Dim lep As New IPEndPoint(lipa.AddressList(0), 11000)
   
   Dim s As New Socket(lep.Address.AddressFamily, SocketType.Stream, ProtocolType.Tcp)
   Try
      
      While True
         allDone.Reset()
         
         Dim buff As Byte() = Encoding.ASCII.GetBytes("This is a test")
         
         Console.WriteLine("Sending Message Now..")
         s.BeginSendTo(buff, 0, buff.Length, 0, lep, New AsyncCallback(AddressOf Async_Send_Receive.SendTo_Callback), s)
         
         allDone.WaitOne()
      End While
   Catch e As Exception
      Console.WriteLine(e.ToString())
   End Try
End Sub 'SendTo

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