Question

我正在使用Discord.js和ytdl开发Discord机器人。但是，每当我键入?play并执行播放命令时，都会引发此错误：

(node:15840) UnhandledPromiseRejectionWarning: TypeError [ERR_INVALID_ARG_TYPE]: The "url" argument must be of type string. Received type undefined
    at URL.parse(url.js:154:11)
    at Object.urlParse [as parse] (url.js:148:13)
    at Object.exports.getURLVideoID (C:\Users\MauSc\Desktop\[MENU DOCS] Bot\node_modules\ytdl-core\lib\util.js:273:22)
    at Function.exports.validateURL(C:\Users\MauSc\Desktop\[MENU DOCS] Bot\node_modules\ytdl-core\lib\util.js:328:20)
    at Object.module.exports.run (C:\Users\MauSc\Desktop\[MENU DOCS] Bot\commands\play.js:18:22)
    at Client.bot.on (C:\Users\MauSc\Desktop\[Menu DOCS] Bot\index.js:51:38)
    at Client.emit (events.js:198:13)
    at MessageCreateHandler.handle (C:\Users\MauSc\Desktop\[MENU DOCS] Bot\node_modules\discord.js\src\client\websocket\packets\handlers\MessageCreate.js:9:34)
    at WebSocketPacketManager.handle (C:\Users\MauSc\Desktop\[MENU DOCS] Bot\node_modules\discord.js\src\client\websocket\packets\WebSocketPacketManager.js:105:65)
    at WebSocketConnection.onPacket (C:\Users\MauSc\Desktop\[MENU DOCS] Bot\node_modules\discord.js\src\client\websocket\WebSocketConnection.js:333:35)
(node:15840) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)
(node:15840) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

这些代码都是从我制作的另一个机器人中复制的，所以我不确定为什么突然出现错误。

这是代码：

const Discord = require("discord.js");
const ytdl = require('ytdl-core');
const streamOptions ={
    seek: 0,
    volume: 1
}

const bot = new Discord.Client({disableEveryone: true});

var musicUrls = [];

bot.on("message", async message => {

module.exports.run = async (bot, message, args) => {
             let url = args[1];
             let voiceChannel = message.guild.channels.find(channel => channel.name === 'Musik Bot');

             if(ytdl.validateURL(url))
             {
                console.log("Valid URL");
                var flag = musicUrls.some(element => element === url);
                if(!flag)
                {
                    musicUrls.push(url);
                    if(voiceChannel != null)
                    {

                        if(voiceChannel.connection)
                        {
                            console.log("Connection exists");
                            const embed = new Discord.RichEmbed();
                            embed.setAuthor(bot.user.username, bot.user.displayAvatarURL);
                            embed.setDescription("Du hast erfolgreich einen Track zu der Playlist hinzugefügt!");
                            message.channel.send(embed);
                        }
                        else {
                            try {
                                const voiceConnection = await voiceChannel.join();
                                await playSong(message.channel, voiceConnection, voiceChannel);
                            }
                            catch(ex)
                            {
                                console.log(ex);
                             }
                         }
                    }

                 }
             }
}
     async function playSong(messageChannel, voiceConnection, voiceChannel)
{
    const stream = ytdl(musicUrls[0], { filter : 'audioonly'});
    const dispatcher = voiceConnection.playStream(stream, streamOptions);

    dispatcher.on('end', () => {
        musicUrls.shift();

        if(musicUrls.length == 0)
            voiceChannel.leave();
        else
        {
            setTimeout(() => {
                 playSong(messageChannel, voiceConnection, voiceChannel);
            }, 1000);
        }
    });
    try {
        if(!message.content.startsWith(prefix)) return;
        let commandfile = bot.commands.get(cmd.slice(prefix.length)) || bot.commands.get(bot.aliases.get(cmd.slice(prefix.length)))
        console.log(commandfile);
        if (commandfile) commandfile.run(bot, message, args)
    } catch (error) {
        console.error(error);
    }
}},


module.exports.config = {
    name: "play",
    aliases: []
});

Answer 1

args[1]在运行代码时未定义，这意味着从不提供。这也会导致url也未定义，然后由于validateURL()需要一个字符串而从ytdl抛出错误。

在继续执行命令之前，请确保存在必需的参数。如果不是，则返回错误消息。例如...

if (!args[1]) {
  return message.channel.send('You must provide a URL!')
    .catch(console.error);
}

ytdl：“ url”参数必须为字符串类型。接收类型未定义

1 个答案: