node . js socket . dropmentry()方法

原文:https://www . geesforgeks . org/node-js-socket-drop membership-method/

socket . DropMemberity()方法是 dgram 模块内一个内置的 Socket 类应用编程接口,用于使内核在特定的组播地址留下一个组播组。

语法:

const socket.dropMembership(multicastAddress[, multicastInterface])

参数:该方法以表示组播地址和组播接口的字符串为参数。

返回值:此方法不返回值。

示例 1: 文件名:index.js

java 描述语言

// Node.js program to demonstrate the
// socket.dropMembership() method

// Importing dgram module
var dgram = require('dgram');

// Creating and initializing client
// and server socket
var client = dgram.createSocket("udp4");
var 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();
})
.bind(1234, () => {

    // Joining a multicast group at
    // multicast address
    server.addMembership('224.0.0.114');

    // leaving a multicast group at
    // multicast address
    server.dropMembership('224.0.0.114');
});

// Client sending message to server
client.send("Hello", 0, 7, 1234, "localhost");

输出:

UDP String: Hello

示例 2: 文件名:index.js

java 描述语言

// Node.js program to demonstrate the
// socket.dropMembership() method

// Importing dgram module
var dgram = require('dgram');

// Creating and initializing client
// and server socket
var client = dgram.createSocket("udp4");
var 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', () => {
    const address = server.address();
    console.log(`server listening
        ${address.address}:${address.port}`);
});

// Binding server with port address
server.bind(1234, () => {

    // Adding a multicast address for
    // others to join
    server.addMembership('224.0.0.114');

    // leaving a multicast group at multicast
    // address by using dropMembership() method
    server.dropMembership('224.0.0.114');
});

// Client sending message to server
client.send("Hello", 0, 7, 1234, "localhost");

输出:

server listening 0.0.0.0:1234
UDP String: Hello

使用以下命令运行 index.js 文件:

node index.js

参考:https://nodejs . org/dist/latest-v 12 . x/docs/API/dgram . html # dgram _ socket _ drop membership _ multicast address _ multicast interface