js judges whether the time is morning, noon, afternoon, evening

      let getTimeState = () => {
                // 获取当前时间
                let timeNow = new Date();
                // 获取当前小时
                let hours = timeNow.getHours();
                // 设置默认文字
                let text = ``;
                // 判断当前时间段
                if (hours >= 0 && hours <= 10) {
                    text = `早上好`;
                } else if (hours > 10 && hours <= 14) {
                    text = `中午好`;
                } else if (hours > 14 && hours <= 18) {
                    text = `下午好`;
                } else if (hours > 18 && hours <= 24) {
                    text = `晚上好`;
                }
                // 返回当前时间段对应的状态
                return text;
            };
            alert(getTimeState())