VB.Net Tutorial/Socket Network/TcpClient
Create TcpClient
<source lang="vbnet">Imports System.Net.Sockets Imports System.Net Imports System.Threading Imports System.Text Public Class Tester
Public Shared Sub Main Dim myTcpClient As New TcpClient() Try myTcpClient.Connect("127.0.0.1", 1234) Catch ex As ArgumentOutOfRangeException Console.WriteLine(ex.Message) Catch ex As SocketException Console.WriteLine(ex.Message) End Try End Sub
End Class</source>
No connection could be made because the target machine actively refused it
Date time client based on TcpClient
<source lang="vbnet">Imports System Imports System.IO Imports System.Net Imports System.Net.Sockets Imports System.Text Public Class DateTimeClient
Public Shared Sub Main() Dim args As String() = Environment.GetCommandLineArgs() Dim serverHost As String = "127.0.0.1" Try Dns.GetHostByName(serverHost) Catch ex As Exception Console.WriteLine("Can not find server, {0}", serverHost) Exit Sub End Try Dim tcpClient As New TcpClient() Dim networkStream As Stream Try tcpClient.Connect(serverHost, 13) networkStream = tcpClient.GetStream() Catch exc As Exception Console.WriteLine("Can not connect to {0}", serverHost) Exit Sub End Try Try If networkStream.CanRead Then Dim recvbytes(tcpClient.ReceiveBufferSize) As Byte Dim i As Integer = networkStream.Read(recvbytes, 0, CInt(tcpClient.ReceiveBufferSize)) Dim datetime As String = Encoding.ASCII.GetString(recvbytes, 0, i) Console.WriteLine("Receive {0} bytes.", i) Console.WriteLine("Current server date/Time: {0}", datetime) Else Console.WriteLine("Network Input Stream is unreadable.") tcpClient.Close() Return End If Catch ec As Exception Console.WriteLine(ec.StackTrace.ToString()) Exit Sub End Try tcpClient.Close() End Sub
End Class</source>
Can not connect to 127.0.0.1