JS achieves five-star praise effect

import Componenet from "./Component.js";
 
export default class Stars extends Componenet {
 
    label;
    STARS_NUM = 5;
    starArr = [];
    score = 0;
    starsCon;
    faceIcon;
    scoreCon;
    index = -1;
    name;
    
    static STARS_LIST={}; //Store all five-star review results on the current page, one product per group. Use the product ID as the key and the product reviews to form an array as the value.
    date=new Date();
 
    constructor(_label,_name) {
        super("div");
        this.name=_name;
        this.label = _label;
        Object.assign(this.elem.style, {
            width:"200px",
            height: "16px",
            float: "left",
            marginRight: "20px",
            marginBottom: "10px",
            fontSize: "12px",
            color: "#666",
            lineHeight: "16px",
            userSelect: "none",
            position: "relative",
            top: "20px",
            left: "20px",
        })
        // Parse the review results stored in the cookie and initialize the score value when creating each review.
        this.initScore();
        // Create the evaluation label part this.createLabel();
        // Create the stars part this.createStars();
        // Create the score part this.createScore();
        // Initialize the star style.
        this.changeStarStyle(this.score-1);
        // Initialize score this.changeScore(this.score);
        // Add mouse rollover and click events.
        this.starsCon.addEventListener("mouseenter", e => this.mouseHandler(e));
        this.starsCon.addEventListener("mouseleave", e => this.mouseHandler(e));
        this.starsCon.addEventListener("mouseover", e => this.mouseHandler(e));
        this.starsCon.addEventListener("click", e => this.clickHandler(e));
        this.date.setFullYear(2021);
    }
    appendTo(_parent){
        super.appendTo(_parent);
        if(!Stars.STARS_LIST[this.name]) Stars.STARS_LIST[this.name]=[];
        Stars.STARS_LIST[this.name].push(this.label+"="+this.score);
    }
    clickHandler(e){
        if(e.target.constructor!==HTMLLIElement) return
        this.index = this.starArr.indexOf(e.target);
        this.score = this.index+1;
        this.changeStarStyle(this.index);
        this.changeScore(this.index+1);
        // Each click will store the result of the comment in the cookie so that it can be read the next time the page is opened. STARS_LIST stores data with label as key and score as value.
        this.storageScore();
    }
    storageScore(){
        for(let prop in Stars.STARS_LIST){
            if(prop === this.name){
                Stars.STARS_LIST[prop].forEach((item,index)=>{
                    if(item.includes(this.label)) Stars.STARS_LIST[prop][index] = this.label+"="+this.score;
                });
            }
        }
        document.cookie="comment="+ JSON.stringify(Stars.STARS_LIST)+";expires="+this.date.toUTCString();
    }
    mouseHandler(e) {
        switch (e.type) {
            case "mouseenter":
                this.faceIcon.style.display = "block";
                break;
            case "mouseleave":
                this.faceIcon.style.display = "none";
                this.changeStarStyle(this.index);
                this.changeScore(this.score);
                break;
            case "mouseover":
                let index = this.starArr.indexOf(e.target);
                this.changeStarStyle(index);
                this.changeScore(index + 1);
                this.changeFaceStyle(index);
                break;
        }
    }
    changeStarStyle(_i) {
        for (let n = 0; n < this.starArr.length; n++) {
            if (n <= _i || n < this.score) {
                this.starArr[n].style.backgroundPositionY = "-16px";
            } else {
                this.starArr[n].style.backgroundPositionY = "0px";
            }
        }
    }
    changeFaceStyle(_i) {
        this.faceIcon.style.left = _i * 16 + "px";
        this.faceIcon.style.backgroundPositionX = (_i + 1) * 20 + "px";
    }
    changeScore(_i) {
        this.scoreCon.textContent = _i + "points";
    }
    createLabel() {
        let label = document.createElement("span");
        Object.assign(label.style, {
            float: "left",
            padding: "0 5px",
        })
        label.textContent = this.label;
        this.elem.appendChild(label);
    }
    createStars() {
        this.starsCon = document.createElement("ul");
        Object.assign(this.starsCon.style, {
            margin: 0,
            padding: 0,
            listStyle: "none",
            width: "80px",
            height: "16px",
            float: "left",
            position: "relative",
        })
        for (let i = 0; i < this.STARS_NUM; i++) {
            let li = document.createElement("li");
            Object.assign(li.style, {
                width: "16px",
                height: "16px",
                float: "left",
                backgroundImage: "url(./star_img/commstar.png)",
            })
            this.starArr.push(li);
            this.starsCon.appendChild(li);
        }
        this.faceIcon = document.createElement("div");
        Object.assign(this.faceIcon.style, {
            width: "16px",
            height: "16px",
            backgroundImage: "url(./star_img/face-red.png)",
            backgroundPositionX: "-80px",
            position: "absolute",
            left: "0",
            top: "-16px",
            display: "none",
        })
        this.starsCon.appendChild(this.faceIcon);
        this.elem.appendChild(this.starsCon);
    }
    createScore() {
        this.scoreCon = document.createElement("div");
        Object.assign(this.scoreCon.style, {
            height: "16px",
            width:"20px",
            float: "left",
            padding: "0 5px",
        })
        this.scoreCon.textContent = this.score + "分",
        this.elem.appendChild(this.scoreCon);
    }
    initScore(){
        // Directly read the cookie to display as follows // comment={"1001":["Product Conformity=5","Shop Service Attitude=0","Express Delivery Speed=0","Courier Service=0","Express Packaging=0"],"1002":["Product Conformity=0","Shop Service Attitude=0","Express Delivery Speed=0","Courier Service=0","Express Packaging=0"]}
 
        // Parse the comment results stored in the cookie.
        if(!document.cookie.includes("comment=")) return
        let o = JSON.parse(document.cookie.match(/(\{.*?\})/)[1]);
        if(!o) return
        // The parsed o is as follows // ["Product Conformity=1", "Shop Service Attitude=0", "Express Delivery Speed=0", "Courier Service=0", "Express Packaging=0"]
        for(let prop in o){
            if(this.name===prop){
                this.score=o[prop].reduce((value,item,index)=>{
                    let arr = item.split("=");
                    if(arr[0].includes(this.label)) value=parseInt(arr[1]);
                    return value;
                },0)
            }
        }
    }
}

import Stars from './js/Stars.js';
let list=["Product Conformity","Shopkeeper Service Attitude","Express Delivery Speed","Courier Service","Express Packaging"];
 
        // let star = new Stars(list[0]);
        // star.appendTo("body");
 
        list.forEach(item=>{
            // Pass in the label and the corresponding product id
            let star = new Stars(item,"1001");
            star.appendTo(".div1");
        })
        list.forEach(item=>{
            let star = new Stars(item,"1002");
            star.appendTo(".div2");
        })