promise的all和race的效果对比

function fun1(){
           return new Promise(_=>{
                setTimeout(()=>{
                    _("1")
                },1000)
           })
        }


function fun2(){
    return new Promise(_=>{
         setTimeout(()=>{
             _("2")
         },2000)
    })
 }

Promise.all([fun1(),fun2()]).then((ret)=>{
       console.log("all",ret);
})

Promise.race([fun1(),fun2()]).then((ret)=>{
   console.log("rece",ret);
})