try/catch 不执行或捕获错误

Question

我正在尝试发出帮助命令，并在发生错误时返回一条消息，这意味着如果用户已关闭 DM 并通知他们，但它似乎不起作用。 它继续发送原始消息，如果出现错误则不会执行 catch function。 我是 javascript 的新手，所以也许我只是做错了或输入了错误的内容。

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 返回 promise ，因此您需要.catch promise，或者将async/await与try/catch块一起使用。

promise是表示异步操作的 object，因此其中发生的错误不会被 try/catch 块捕获。

 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?')
    });

altnernative，如果你使用async/await是这样的：

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?')
    }
}