如何让我的discord.js机器人在其他通道中读/写？

npm install discord.js

const Discord = require('discord.js');
const client = new Discord.Client();

client.on('ready', () => {
  console.log(`Logged in as ${client.user.tag}!`);
});

client.on('message', msg => {
  if (msg.content === 'ping') {
    msg.reply('Pong!');
  }
});

client.login('your-token-goes-here');

const channelID = 'your-channel-id-goes-here';

client.channels.fetch(channelID)
  .then(channel => {
    channel.messages.fetch()
      .then(messages => {
        messages.forEach(message => {
          console.log(message.content);
        });
      })
      .catch(console.error);
  })
  .catch(console.error);

const channelID = 'your-channel-id-goes-here';
const messageContent = 'Hello, world!';

client.channels.fetch(channelID)
  .then(channel => {
    channel.send(messageContent)
      .then(sentMessage => {
        console.log(`Message sent: ${sentMessage.content}`);
      })
      .catch(console.error);
  })
  .catch(console.error);