无法解析函数内部的承诺

Question

这是我的一段原始代码，为什么我不能以这种方式解析指令函数？

实际上我曾经解决过这样的承诺，其他功能的相同代码以前工作过。

我无法在没有手的情况下找到原因和解决方案。

 var instructResolve; async function instruct(location, category){ switch(location) { case 'User_Was_Silent': console.log('Start!') await audioPlay(); console.log('After audioPlay await is done, then resolve instruct!') instructResolve(); break; } return new Promise((resolve) => { instructResolve = resolve; }); }; function audioPlay(source){ console.log('await audioPlay..') return new Promise((resolve) => { setTimeout(function(){ console.log('audioPlay resolved..') resolve(); }, 5000) }); } recognize(); async function recognize(){ await instruct('User_Was_Silent'); //After resolving instruct do stuff like logging some success message on the console console.log('Final log success!') }

在recognize函数中，我正在等待instruct函数解析，然后我们执行诸如在控制台上记录一些成功消息之类的操作，但是由于由于某种原因recognize无法解析我们无法看到console.log('Final log success!')

更新：我有一个类似的代码，可以正常工作，没有任何问题，我已经实现了承诺并像上面的代码一样解决，但它有效！

 var updateGuiderResolve; function updateGuider(state, guide, lower){ console.log('updateGuider...') switch(state) { case 'default': stateReveal("default"); break; } return new Promise((resolve) => { updateGuiderResolve = resolve; }); } function stateReveal(state){ console.log('stateReveal...') setTimeout(function(){ speak(); }, 5000); } function speak(){ console.log('speak...') setTimeout(function(){ console.log('updateGuiderResolve...') updateGuiderResolve() }, 5000); } async function tutor(){ await updateGuider('default'); console.log('final...') } tutor()

Answer 1

我可以在代码库中看到 2 个问题。

一个是

instructResolve(); // It's not function, I think as it's only declared at first.

第二个是

await instruct('User_Was_Silent'); // This does not need to add await as it's already async function. Simply call instruct('User_Was_Silent'); and missing second param in this function.

 var instructResolve; async function instruct(location, category=null){ switch(location) { case 'User_Was_Silent': console.log('Start!') await audioPlay(); console.log('After audioPlay await is done, then resolve instruct!') break; } }; function audioPlay(source){ console.log('await audioPlay..') return new Promise((resolve) => { setTimeout(function(){ console.log('audioPlay resolved..') resolve(); }, 5000) }); } async function recognize(){ await instruct('User_Was_Silent'); //After resolving instruct do stuff like logging some success message on the console console.log('Final log success!') } recognize();

Answer 2

尝试像这样在 Promise 内部调用 instructResolve ：

var instructResolve;
async function instruct(location, category){
 switch(location) {
   case 'User_Was_Silent':
   console.log('Start!')
   await audioPlay();
   console.log('After audioPlay await is done, then resolve instruct!')
   break;
 }

 return new Promise((resolve) => { 
    instructResolve = resolve;
    instructResolve();
 });
}

Answer 3

有一个这样的解决方案，但我想知道为什么问题的代码不起作用？

 var instructResolve; async function instruct(location, category){ return new Promise(async (resolve) => { switch(location) { case 'User_Was_Silent': console.log('Start!') await audioPlay(); console.log('After audioPlay await is done, then resolve instruct!') resolve(); break; } }); }; function audioPlay(source){ console.log('await audioPlay..') return new Promise((resolve) => { setTimeout(function(){ console.log('audioPlay resolved..') resolve(); }, 5000) }); } async function recognize(){ await instruct('User_Was_Silent'); //After resolving instruct do stuff like logging some success message on the console console.log('Final log success!') } recognize();