Discord.js中如何存储命令选项并实现echo命令机器人回复？

问题描述 #

我是Discord.js新手，想要实现echo命令：获取命令的input选项内容并让机器人回复，同时想知道能不能把命令选项存入变量。当前运行代码时出现报错：TypeError: Cannot read properties of undefined (reading 'ephemeral')

项目代码及报错日志 #

package.json #

{
  "name": "bot",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}

index.js #

const fs = require('node:fs');
const path = require('node:path');
const {Client,GatewayIntentBits, Collection} = require('discord.js');
const {token} = require('./config.json');
const { execute } = require('./commands/ping');
const ping = require('./commands/ping');

const client = new Client({intents: [GatewayIntentBits.Guilds]});

client.commands = new Collection();
const commandPath = path.join(__dirname, 'commands');
const commandFiles = fs.readdirSync(commandPath).filter(file => file.endsWith('.js'));

for (const file of commandFiles) {
    const filePath = path.join(commandPath, file);
    const command = require(filePath);

    client.commands.set(command.data.name, command);
}

client.once('ready',()=> {
    console.log("ready");
});

client.on('interactionCreate', async interaction => {
    if(!interaction.isChatInputCommand()) return;
    
    const command = client.commands.get(interaction.commandName)

    if(!command) return;
    try {
        await command.execute(interaction);
    } catch(error) {
        console.error(error);
        await interaction.reply({content: "there was an error while executing this command", ephemeral: true});
    }
});

client.login(token);

echo.js #

const {SlashCommandBuilder} = require('discord.js');

module.exports = {
    data: new SlashCommandBuilder()
        .setName('echo')
        .setDescription('returns input')
        .addStringOption(option =>
            option.setName('input')
                .setDescription("the option to echo back")
                .setRequired(true)),
            
    async execute(interaction) {
        await interaction.reply();
    }
}

ping.js #

const {SlashCommandBuilder} = require('discord.js');

module.exports = {
    data: new SlashCommandBuilder()
        .setName('ping')
        .setDescription('replies with pong'),
    async execute(interaction) {
        await interaction.reply("pong!")
    }
}

deploy-commands.js #

const {REST} = require("@discordjs/rest");
const {Routes} = require("discord.js");
const {clientId, guildId, token} = require("./config.json");
const path = require("node:path");
const fs = require("node:fs");

const commands = [];
const commandPath = path.join(__dirname, 'commands');
const commandFiles = fs.readdirSync(commandPath).filter(file => file.endsWith('.js'));

for (const file of commandFiles) {
    const filePath = path.join(commandPath, file);
    const command = require(filePath);
    commands.push(command.data.toJSON());
}

const rest = new REST({version: 10}).setToken(token);

rest.put(Routes.applicationGuildCommands(clientId, guildId), {body:commands})
    .then(() => console.log("registered commands"))
    .catch(console.error);

config.json #

{
    "token": "hidden",
    "clientId": "1009394510117212162",
    "guildId": "1009401102929768479"
}

报错日志 #

C:\Users\perry\Desktop\bot>node . ready TypeError: Cannot read properties of undefined (reading 'ephemeral')
at ChatInputCommandInteraction.reply (C:\Users\perry\node_modules\discord.js\src\structures\interfaces\InteractionResponses.js:102:30)
at Object.execute (C:\Users\perry\Desktop\bot\commands\echo.js:14:27)
at Client. (C:\Users\perry\Desktop\bot\index.js:32:23)
at Client.emit (node:events:527:28)
at InteractionCreateAction.handle (C:\Users\perry\node_modules\discord.js\src\client\actions\InteractionCreate.js:81:12)
at Object.module.exports [as INTERACTION_CREATE] (C:\Users\perry\node_modules\discord.js\src\client\websocket\handlers\INTERACTION_CREATE.js:4:36)
at WebSocketManager.handlePacket (C:\Users\perry\node_modules\discord.js\src\client\websocket\WebSocketManager.js:352:31)
at WebSocketShard.onPacket (C:\Users\perry\node_modules\discord.js\src\client\websocket\WebSocketShard.js:481:22)
at WebSocketShard.onMessage (C:\Users\perry\node_modules\discord.js\src\client\websocket\WebSocketShard.js:321:10)
at WebSocket.onMessage (C:\Users\perry\node_modules\ws\lib\event-target.js:199:18)

解决方法 #

1. 报错原因及修复 #

报错根源在echo.js的execute方法：调用await interaction.reply();时未传入任何参数。Discord.js的reply()方法会尝试读取参数对象中的ephemeral属性，无参数时参数为undefined，因此触发该错误。

2. 实现Echo命令并获取选项 #

修改echo.js的execute方法，通过interaction.options.getString('input')获取用户输入的选项内容，完成回复逻辑：

const {SlashCommandBuilder} = require('discord.js');

module.exports = {
    data: new SlashCommandBuilder()
        .setName('echo')
        .setDescription('返回输入内容')
        .addStringOption(option =>
            option.setName('input')
                .setDescription("要返回的内容")
                .setRequired(true)),
            
    async execute(interaction) {
        // 将命令选项内容存入变量
        const userInput = interaction.options.getString('input');
        // 直接回复用户输入内容
        await interaction.reply(userInput);
        // 若需私密回复（仅用户可见），可传入对象参数：
        // await interaction.reply({ content: userInput, ephemeral: true });
    }
}

3. 命令选项存入变量的说明 #

完全可以将命令选项存入变量，上述代码中已将input选项内容存入userInput变量，你可基于此变量进行后续操作，比如内容修改、数据库存储等。

4. 额外注意事项 #

• 修改echo.js后无需重新运行deploy-commands.js，仅执行逻辑变更不影响命令结构。
• 确保Discord.js版本为v10（代码中REST({version: 10})已指定），版本不一致可能引发其他问题。

内容的提问来源于stack exchange，提问作者mel.pear