事件循环题整理

1

setTimeout(() => {
  console.log(1);
}, 1000)
new Promise(function(resolve){
    console.log(2);
    for(var i = 0; i < 10000; i++){
        i == 99 && resolve();
    }
}).then(function(){
    console.log(3)
});
console.log(4)

2

setTimeout(() => {
  console.log(1)
}, 0)

const P = new Promise((resolve, reject) => {
  console.log(2)
  setTimeout(() => {
      resolve()
      console.log(3)
  }, 0)
})

P.then(() => {
  console.log(4)
})
console.log(5)

3

setTimeout(() => {
    console.log('time1');
}, 1 * 2000);

Promise.resolve()
.then(function() {
    console.log('promise1');
}).then(function() {
    console.log('promise2');
});


async function foo() {
    await bar()
    console.log('async1 end')
}
foo()

async function errorFunc () {
    try {
        await Promise.reject('error!!!')
    } catch(e) {
        console.log(e)
    }
    console.log('async1');
    return Promise.resolve('async1 success')
}
errorFunc().then(res => console.log(res))

function bar() {
    console.log('async2 end') 
}

console.log('script end');```