天天快看：JS+CSS快速实现新手引导效果

let maskIntroduceManage = new MaskIntroduceManage([    new MaskIntroduceItem("one","人生若只如初见"),    new MaskIntroduceItem("two","何事秋风悲画扇"),    new MaskIntroduceItem("five","等闲却变故人心"),    new MaskIntroduceItem("six","骊山语罢清宵半"),    new MaskIntroduceItem("four","却道故人心易变"),    new MaskIntroduceItem("finally","谢谢大家支持！")])maskIntroduceManage.benginIntroduce()

    纳    兰    容    若    作    词
    谢谢
<script src="./maskIntroduce.js"></script><script>let maskIntroduceManage = new MaskIntroduceManage([    new MaskIntroduceItem("one","人生若只如初见"),    new MaskIntroduceItem("two","何事秋风悲画扇"),    new MaskIntroduceItem("five","等闲却变故人心"),    new MaskIntroduceItem("six","骊山语罢清宵半"),    new MaskIntroduceItem("four","却道故人心易变"),    new MaskIntroduceItem("finally","谢谢大家支持！")])maskIntroduceManage.benginIntroduce()</script>

// 单元信息modelclass MaskIntroduceItem {    // 需要引导的dom的ID    id    // 需要引导的dom功能描述    warming    constructor(id,warming){        this.id = id        this.warming = warming    }}// 遮罩操作类class MaskIntroduceManage {    // 消息展示类集合    maskIntroduceItems    // 遮罩层    el    // 遮罩层提示框    warmingEl    // 指引肩头    guidanceEl    // 展示的第几个    currentShowIndex = 0    // 记录window事件    windowEvent = null        constructor(maskIntroduceItems){        this.maskIntroduceItems = maskIntroduceItems    }        // 添加消息展示类    addIntroduceItem(introduceItem){        this.maskIntroduceItems.push(introduceItem)    }        // body增加遮罩    addMaskToBody(){        //添加遮罩框        this.el = document.createElement("div")        this.el.style.cssText = "position: fixed;background: transparent;outline:rgba(0, 0, 0, 0.5) 3500px solid;"        let body = document.getElementsByTagName("body")[0]        body.appendChild(this.el)        //添加提示框        this.warmingEl = document.createElement("div")        this.warmingEl.style.cssText = "position:fixed;width:100px;background:white;border-radius: 10px;padding: 30px;font-size: 14px;"        body.appendChild(this.warmingEl)        //添加指引箭头        this.guidanceEl = document.createElement("div")        this.guidanceEl.style.cssText = "position:fixed;width: 14px; height: 13px; background-color: white;clip-path: polygon(50% 0,100% 100%,0 100%);"        body.appendChild(this.guidanceEl)        //设置body禁止滚动        body.style.overflow = "hidden"        //保留window事件        if(window.onclick){            this.windowEvent = window.onclick        }        window.onclick = ()=>{            this.nextIntroduce()        }    }    // 开始引导    benginIntroduce(){        this.addMaskToBody()        this.nextIntroduce()    }        // 下一步    nextIntroduce(){        let maskIntroduceItem = this.maskIntroduceItems.length > 0 ? this.maskIntroduceItems[this.currentShowIndex] : null        if(!maskIntroduceItem){            return        }        let needIntroduceEl = document.getElementById(maskIntroduceItem.id)        //遮罩层的镂空位置        this.el.style.width = needIntroduceEl.offsetWidth + "px"        this.el.style.height = needIntroduceEl.offsetHeight + "px"        this.el.style.top = this.getElementPosition(needIntroduceEl).top + "px"        this.el.style.left = this.getElementPosition(needIntroduceEl).left + "px"        //设置对应倒角，但是由于背景颜色是透明的，所以，没有效果（???）        //this.el.style.borderRadius = window.getComputedStyle(needIntroduceEl,null)["border-radius"]        this.currentShowIndex ++        //指引箭头位置        let guidanceElLeft = this.getElementPosition(needIntroduceEl).left + needIntroduceEl.offsetWidth / 2.0        this.guidanceEl.style.top = this.getElementPosition(needIntroduceEl).top + needIntroduceEl.offsetHeight + 20 + "px"        this.guidanceEl.style.left = guidanceElLeft + "px"        //提示框的位置        this.warmingEl.style.top = this.getElementPosition(this.guidanceEl).top + this.guidanceEl.offsetHeight - 4 + "px"        let warmingElLeft = this.getElementPosition(needIntroduceEl).left - ((this.warmingEl.offsetWidth - needIntroduceEl.offsetWidth) / 2.0)        if(warmingElLeft < 0){            warmingElLeft = this.getElementPosition(needIntroduceEl).left + 10        }        if(warmingElLeft + this.warmingEl.offsetWidth > document.getElementsByTagName("body")[0].offsetWidth){            warmingElLeft = warmingElLeft - 10 - (this.warmingEl.offsetWidth - needIntroduceEl.offsetWidth) / 2.0        }        this.warmingEl.style.left = warmingElLeft + "px"        this.warmingEl.innerHTML = maskIntroduceItem.warming        //最后一个展示完恢复window点击事件        if(this.currentShowIndex >= this.maskIntroduceItems.length){            setTimeout(() => {                //移除当前遮罩                this.el.remove()                //移除当前提示框                this.warmingEl.remove()                //移除箭头                this.guidanceEl.remove()                //设置body可以滚动                document.getElementsByTagName("body")[0].style.overflow = "auto"                //恢复window事件                if(this.windowEvent){                    window.onclick = this.windowEvent                }            }, 2000);        }    }    // 获取元素在屏幕的位置    getElementPosition(element){        var top = element.offsetTop        var left = element.offsetLeft        var currentParent = element.offsetParent;        while (currentParent !== null) {            top += currentParent.offsetTop            left += currentParent.offsetLeft            currentParent = currentParent.offsetParent        }        return {top,left}    }}