B4X

Socket Send and Receive BinData

Demonstrates the Chilkat Socket ReceiveBdN and SendBd methods. 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 26 bytes contained in a Chilkat BinData
Dim bdToSend As ChilkatBinData
bdToSend.Initialize
Dim i As Int = 0
Dim byteVal As Int = 65
Do While i < 26
    bdToSend.AppendByte(byteVal)
    byteVal = byteVal + 1
    i = i + 1
Loop
'  Send the contents of the BinData
'  Pass zero's in the 2nd and 3rd arguments to send the entire contents of the BinData.
sock.SendBd(bdToSend, 0, 0)

'  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 bytes back..
Dim bdRecv As ChilkatBinData
bdRecv.Initialize
'  Receive the 26 bytes previously sent, plus the LF char.
success = sock.ReceiveBdN(27, bdRecv)
If success = False Then
    Log(sock.LastErrorText)
    Return
End If


'  Show the contents of bdRecv in hex format
Log(bdRecv.GetEncoded("hex"))

'  Output:  4142434445464748494A4B4C4D4E4F505152535455565758595A0A