The socket.bind() method is an inbuilt application programming interface of class Socket within dgram module which is used to bind the particular data gram server to a particular port with some required information.
Syntax:
const socket.bind(options[, callback])
Parameters: This method takes the following parameter:
- option: It can use the following parameters-
- port: port value.
- address: address
- exclusive: Boolean value true or false.
- fd: Integer value.
- callback: Callback function for further operation.
Return Value: This method returns the object which contains the address information for the socket.
Example 1: In this example, we will see the use of socket.bind() method.
Filename: index.js
// Node.js program to demonstrate the
// server.bind() method
// Importing dgram module
const dgram = require('dgram');
// Creating and initializing client
// and server socket
let client = dgram.createSocket("udp4");
let server = dgram.createSocket("udp4");
// Catching the message event
server.on("message", function (msg) {
// Displaying the client message
process.stdout.write("UDP String: " + msg + "\n");
// Exiting process
process.exit();
})
// Binding server with port
.bind(1234, () => {
// Getting the address information
// for the server by using
// address() method
const address = server.address()
// Display the result
console.log(address);
});
// Client sending message to server
client.send("Hello", 0, 7, 1234, "localhost");
Output:
{ address: '0.0.0.0', family: 'IPv4', port: 1234 }
UDP String: Hello
Example 2: In this example, we will see the use of socket.bind() method.
Filename: index.js
// Node.js program to demonstrate the
// server.bind() method
// Importing dgram module
const dgram = require('dgram');
// Creating and initializing client
// and server socket
let client = dgram.createSocket("udp4");
let server = dgram.createSocket("udp4");
// Catching the message event
server.on("message", function (msg) {
// Displaying the client message
process.stdout.write("UDP String: " + msg + "\n");
// Exiting process
process.exit();
});
// Catching the listening event
server.on('listening', () => {
// Getting address information for the server
const address = server.address();
// Display the result
console.log(`server listening
${address.address}:${address.port}`);
});
// Binding server with port address
// by using bind() method
server.bind(1234, () => {
// Adding a multicast address for others to join
server.addMembership('224.0.0.114');
});
// Client sending message to server
client.send("Hello", 0, 7, 1234, "localhost");
Output:
server listening 0.0.0.0:1234 UDP String: Hello
Run the index.js file using the following command:
node index.js
Reference:https://nodejs.org/dist/latest-v12.x/docs/api/dgram.html#dgram_socket_bind_options_callback