封装一个obj对象 实现 obj 链式调用,异步等待settimeOut之后继续调用

Question

例:obj.write("1").await(1000).write("2");// 打印 1// 等待 await 时长之后打印 2### 题目描述

Answer 1

class Obj {    constructor () {      this.sleep = 0
    }

    write (str) {      if (this.sleep) {
        setTimeout(() => {
            console.log(str)
          },          this.sleep)
      } else {
        console.log(str)
      }      return this
    }

    await (time) {      this.sleep += time      return this
    }
  }  const obj = new Obj()

  obj.write('1').await(1000).write('2').await(3000).write(3)

Answer 2

function Delay() {    this.queue = Promise.resolve();
}
Delay.prototype.write = function() {    var args = arguments;    var _this = this;    this.queue = this.queue.then(function() {        console.log.apply(_this, args);
    });    return this;
};
Delay.prototype.await = function(time) {    this.queue = this.queue.then(function() {        return new Promise(function(resolve) {
            setTimeout(resolve, time);
        });
    });    return this;
};var obj = new Delay();
obj.write("1").await(1000).write("2");