How to make a value in a function global node.js?

Question

Node.js

the res value is returned in the function, how can this value be used outside the function?

Answer 1

etozh callback - so will never work.
at you at first create will be caused, then console.log. but whether the callback between them will be called - this is written with a pitchfork on the water.
```
ttttt.create({...}), function (err, res) {
if (err) throw err;
console log(res);
return res;
});
```

Answer 2

Through async should work. You only need nodejs 7.7.4, it works for me on this version.

var output;
var genNum = async function () {
    return new Promise((resolve, reject) => {
        setTimeout(() => {
            return resolve(Math.random())
        }, 1000)
    })
}

output = await gennum();
console.log(output);

I used it here , you can see it there.