try/catch 不执行或捕获错误

Question

I'm trying to make a help command, and return a message if an error occurs, meaning if the user has DMs closed and inform them about it, but it just doesn't seem to work. It goes on with sending the original messages and doesn't execute the catch function if it gets an error. I'm overall new to javascript, so maybe I've just done it wrong or mistyped something.

try {
    message.author.send('Here\'s a list of my commands:')
    message.author.send('Commands')
    message.channel.send('I sent you a dm with all the commands. If you haven\'t received it, check if your dms are open.')
} catch (error) {
    message.channel.send('Couldn\'t send you a message. Are your dms open?')

Answer 1

send returns a promise , so you'd need to either .catch the promise, or use async/await with a try/catch block.

A promise is an object that represents an async operation, so an error that occurs inside it, won't be caught by a try/catch block.

 message.author.send('Here\'s a list of my commands:')
 message.author.send('Commands')
 message.channel.send('I sent you a dm with all the commands. If you haven\'t received it, check if your dms are open.')
    .catch((error) => {
        message.channel.send('Couldn\'t send you a message. Are your dms open?')
    });

The altnernative, if you're using async/await is like this:

async function whatever() {
    ... 
    try {
        await message.author.send('Here\'s a list of my commands:')
        await message.author.send('Commands')
        await message.channel.send('I sent you a dm with all the commands. If you haven\'t received it, check if your dms are open.')
    } catch (err) {
        await message.channel.send('Couldn\'t send you a message. Are your dms open?')
    }
}