Node.js

Socket Receive String Until Specific Byte Value is Received

Demonstrates the Chilkat Socket ReceiveStringUntilByte method. Node.js

NODEJS_PRELUDE

function chilkatExample() {

    var success = false;

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

    var sock = new chilkat.Socket();

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

    var useTls = false;
    var port = 4242;
    var maxWaitMs = 5000;
    success = sock.Connect("tcpbin.com",port,useTls,maxWaitMs);
    if (success == false) {
        console.log(sock.LastErrorText);
        return;
    }

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

    //  Send some strings, each terminated by a 0 byte.
    sock.SendString("This is the 1st string");
    sock.SendByte(0);
    sock.SendString("This is string number 2");
    sock.SendByte(0);

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

    //  Now let's receive what is echoed back....
    //  Receive each string and the NULL byte.
    //  The call to ReceiveStringUntilByte will receive incoming data until the lookForByte is encountered.
    //  The lookForByte is receive and discarded (it is not returned in the string)
    var lookForByte = 0;
    var s1 = sock.ReceiveStringUntilByte(lookForByte);
    if (sock.LastMethodSuccess == false) {
        console.log(sock.LastErrorText);
        return;
    }

    console.log(s1);

    var s2 = sock.ReceiveStringUntilByte(lookForByte);
    if (sock.LastMethodSuccess == false) {
        console.log(sock.LastErrorText);
        return;
    }

    console.log(s2);

    //  The echo server will also echo back the final LF
    sock.ReceiveByte(true);
    maxWaitMs = 100;
    sock.Close(100);

    //  Output:
    //  This is the 1st string
    //  This is string number 2

}

chilkatExample();