B4X

TCP Socket Send Byte and Receive Byte

Demonstrates the Chilkat Socket ReceiveByte and SendByte method. B4X

Dim success As Boolean = False

'  This example requires the Chilkat API to have been previously unlocked.
'  See Global Unlock Sample for sample code.

Dim sock As ChilkatSocket
sock.Initialize("sock")

'  --------------------------------------------------------------------
'  This example uses the public TCP echo service at https://tcpbin.com/
'  --------------------------------------------------------------------

Dim useTls As Boolean = False
Dim port As Int = 4242
Dim maxWaitMs As Int = 5000
success = sock.Connect("tcpbin.com", port, useTls, maxWaitMs)
If success = False Then
    Log(sock.LastErrorText)
    Return
End If


'  Wait a max of 2 seconds for a response..
sock.MaxReadIdleMs = 2000

'  Send a byte.
sock.SendByte(96)

'  The tcpbin.com echo server only echoes after receiving an LF (linefeed char)
sock.SendByte(10)

'  The echo server will echo back whatever is sent to it.
'  We should be able to read the same byte back..
'  After successfully reading, the byte value is available in the ReceivedInt property.
Dim treatAsUnsignedInt As Boolean = True
success = sock.ReceiveByte(treatAsUnsignedInt)
If success = False Then
    Log(sock.LastErrorText)
    Return
End If


'  Let's look at the value of the byte received.  It should be 96.
Log(sock.ReceivedInt)

'  The echo server also echoed the LF back.
success = sock.ReceiveByte(treatAsUnsignedInt)
'  Assuming success..

'  Should be decimal 10.
Log(sock.ReceivedInt)