异步功能 - 等待不等待承诺 [英] async function - await not waiting for promise

问题描述

我正在尝试学习async-await。在此代码中 -

I'm trying to learn async-await. In this code -

const myFun = () => {
    let state = false;

    setTimeout(() => {state = true}, 2000);

    return new Promise((resolve, reject) => {
        setTimeout(() => {
            if(state) {
                resolve('State is true');
            } else {
                reject('State is false');
            }
        }, 3000);
    });
}

const getResult = async () => {
    return await myFun();
}

console.log(getResult());

为什么我输出为 -

why am I getting output as -

Promise { <pending> }

而不是某些价值？不应该 getResult（）函数等待 myFun（）函数解析它的promise值？

Instead of some value? Shouldn't the getResult() function wait for myFun() function resolve it's promise value?

推荐答案

如果您正在使用async / await，则所有调用都必须使用Promises或async / await。你不能只是神奇地从同步电话中获得异步结果。

If you're using async/await, all your calls have to use Promises or async/await. You can't just magically get an async result from a sync call.

您的最终通话需要是：

getResult().then(response => console.log(response));

或类似：

(async () => console.log(await getResult()))()

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