如何在完成所有setTimeout函数后调用函数

Question

How to call the second function after the all previous functions is done.

function first() {
    // code here
    setTimeout( function() {
        // code here
    }, 1000);

    // code here
    setTimeout( function() {
        // code here
    }, 3000);

    // code here
    setTimeout( function() {
        // code here
    }, 3800);
}

function second() {
    // code here
}

first();
first();
second();
first();
second();

It seems all functions executed in the same time.
Thanks a lot.

Answer 1

If you need to call a specific function after the last timeout, I think this will point you in the right direction. Of course, it can be written better, with reusable "class" etc.

 function myTimeout(f,t) { var p = new Promise(resolve=>{ setTimeout(()=>{ resolve(f.apply(this,[])); }, t); }); //return p.promise(); return p; } function first() { var numberOfTimeouts = 3 // code here myTimeout(()=>{ // code here console.log('a') }, 1000).then(()=>{ numberOfTimeouts--; if (!numberOfTimeouts) second() }); // code here myTimeout( function() { console.log('b') }, 3000).then(()=>{ numberOfTimeouts--; if (!numberOfTimeouts) second() }); // code here myTimeout( function() { console.log('c') }, 3800).then(()=>{ numberOfTimeouts--; if (!numberOfTimeouts) second() }); } function second() { console.log('d') } first();