2021-09-02 JS Async/Await with Promise

 for循环,  异步变同步

async function test(){    
    for(let i=0; i < 3; i++){     
        // KEEP IT IN SYNC
        await A().then(async res => {
            console.log('--1');
            await B().then(res => {
                console.log('--2');
            })                   
        }).catch(err =>{
            console.log(err);
        })  
    }
    console.log('Finish')    
};

function A(){
   return new Promise(function(resolve, reject){
   		setTimeout(()=>{
      	console.log('Run A')
        resolve(true);
      },1000)
   })
}

function B(){
   return new Promise(function(resolve, reject){
   		setTimeout(()=>{
      	console.log('Run B')
        resolve(true);
      },1000)
   })
}

test();