处理承诺拒绝以使函数退出的正确方法是什么？

Question

假设我有这样的代码：

function doSomething() {
const foo = await new Promise((resolve, reject) => {
//...
reject();
}).catch(error => {
//I'd like to exit the doSomething function since the promise rejected
return;//This only exists the this arrow funtion
});
console.log('Should not get to here if foo rejects');
}

如果foo返回一个被拒绝的promise，那么我想退出doSomething()，但上面的代码并不能做到这一点。相反，由于error被捕获，代码将继续。

如果我没有catch拒绝的承诺，那么我会得到一个错误：UnhandledPromiseRejectionWarning:

function doSomething() {
const foo = await new Promise((resolve, reject) => {
//...
reject();
});
console.log('Should not get to here if foo rejects');
}

我知道我可以做到，但这感觉很混乱：

function doSomething() {
let exitFunction = false;
const foo = await new Promise((resolve, reject) => {
//...
reject();
}).catch(error => {
//I'd like to exit the doSomething function since the promise rejected
exitFunction = true;
});
if (exitFunction) {
return;
}
console.log('Should not get to here if foo rejects');
}

那么，处理这样的事情最好的方法是什么呢？如果能做到这一点就太好了：

function doSomething() {
const foo = await new Promise((resolve, reject) => {
//...
reject();
});
if (foo.rejected) {
return;
}
console.log('Should not get to here if foo rejects');
}

甚至这个：

function doSomething() {
const foo = await new Promise((resolve, reject) => {
//...
reject();
}).catch(error => {
return function2;//Sort of like JS's `break loop2;`
});
console.log('Should not get to here if foo rejects');
}

有人感觉到我的痛苦吗？如果有，最好(最干净)的方法是什么？

Answer 1

如果您在async function中处理承诺，我建议使用try/catch

function promiseFunc() {
return new Promise((resolve, reject) => {
//...
reject("error!");
});
}
async function doSomething() {
try {
const foo = await promiseFunc();
} catch (err) {
console.log(err);
return;
}
console.log("Should not get to here if foo rejects");
}
doSomething();

Answer 2

我认为您只是误解了return在第一个代码中返回到
的位置
return返回到foo
这就是它继续的原因

您可以使用foo来捕获像这样的返回结果

async function doSomething() {
let foo = await new Promise((resolve, reject) => {
reject();
}).catch(error => {
return false;
});
if(!foo) return console.log("rejected and stopped");
console.log('Should not get to here if foo rejects');
}
doSomething()

或者像这个

async function doSomething() {
if (!
await new Promise((resolve, reject) => {
reject();
}).catch(error => {
return false;
})
) return console.log("rejected and stopped");;
console.log('Should not get to here if foo rejects');
}
doSomething()