javascript setTimeout函数的异步实现

Posted 2021-05-03

const setAsyncTimeout = (cb, timeout = 0) => new Promise(resolve => {
    setTimeout(() => {
        cb();
        resolve();
    }, timeout);
});

// Instead of nesting setTimeout functions...
const doStuff = () => {
    setTimeout(() => {
        // Do stuff
    
        setTimeout(() => {
            // Do more stuff
    
            setTimeout(() => {
                // Do even more stuff
            }, 2000);
        }, 500);
    }, 1000);
};

doStuff();

// await them in an async function
const doStuffAsync = async () => {
    await setAsyncTimeout(() => {
        // Do stuff
    }, 1000);

    await setAsyncTimeout(() => {
        // Do more stuff
    }, 500);
    
    await setAsyncTimeout(() => {
        // Do even more stuff
    }, 2000);
};

doStuffAsync();