promise链式调用

//不了解promise可以先去看看，了解后再来相信大家读能看的懂function Promise1(resolve, reject) {    setTimeout(function() {        resolve(‘1‘);    },5000);}

function Promise2(resolve, reject) {    setTimeout(function() {        resolve(‘2‘);    },5000);}

function Promise3(resolve) {    setTimeout(function() {        resolve(‘3‘);    },5000);}new Promise(Promise1).then(function(val){    console.log(val);    return new Promise(Promise2);}).then(function(val){    console.log(val);    return  new Promise(Promise3);}).then(function(val){    console.log(val);});

原文地址：https://www.cnblogs.com/zou1234/p/8723955.html