设置超时抽出时间来调用函数,但代码需要等到回报还没有返回
var test = new Promise((resolve,reject)=>{
resolve(2);
})
test.then(r).then(s).then(t).then((tt)=>{
console.log(tt);
});
function r(r){
setTimeout(()=>{
r=r+1;
return(r);
},2000)
}
function s(r){
r=r+1;
return(r);
}
function t(r){
r=r+1;
return(r);
}
你是不是等待setTimeout函数来完成
var test = new Promise((resolve, reject) => {
return resolve(2);
})
test.then(r).then(s).then(t).then((tt) => {
console.log(tt);
});
function r(r) {
return new Promise((resolve, reject) => {
setTimeout(() => {
r = r + 1;
return resolve(r);
}, 2000)
})
}
function s(r) {
r = r + 1;
return r;
}
function t(r) {
r = r + 1;
return r;
}