javascript - 如何使 setTimeout() 像在 for 循环中一样工作？

Question

如何使 setTimeout() 像在 for 循环中一样工作？喜欢这段代码

function hello() {
    for (let index = 0; index < 3; index++) {
        setTimeout(function () {
            console.log('What\'s up!')
        }, 3000)
        console.log('Yo')
    }
}

hello()

记录

Yo
Yo
Yo
What's up!
What's up!
What's up!

我怎样才能让它成为日志

Yo
What's up(after 3 sec)
Yo
What's up(after 3 sec)
Yo
What's up(after 3 sec)

感谢您的帮助。

Answer 1

一种方法是这样的:

function hello() {
    for (let index = 1; index <= 3; index++) {
        setTimeout(function () {
            console.log('What\'s up!')
        }, 3000 * index)
        setTimeout(function () {
            console.log('Yo')
        }, 3000 * (index - 1))
    }
}
hello()

我基本上利用 for 循环索引为每个 console.log 调用提供不同的延迟。请注意“Yo”总是比“What's up”早 3000 毫秒。