承诺不等到完成 [英] Promise not waiting to finish

问题描述

我今天看了很多例子.他们似乎建议以下代码应按链执行:

I looked at many examples today. They seem to suggest that the following code should be executed in chain:

let f = () => {
    return new Promise((res, rej) => {
        console.log('entering function');
        setTimeout(() => {
            console.log('resolving');
            res()
        }, 2000)
    });
};

Promise.resolve()
    .then(f())
    .then(f());

预期输出为:

entering function
resolving
entering function
resolving

但不是.输出是

entering function
entering function
resolving
resolving

，我不知道为什么.任何帮助将不胜感激.

and I can't figure out why. Any help will be much appreciated.

推荐答案

尝试使用then(f)而不是then(f())

then需要一个功能.

您也可以执行then(()=>f())

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