技術標籤：Vue獲取元素與螢幕的距離獲取滑鼠與螢幕的距離css放大圖片

目錄

封裝元件 s-imgZoom.vue

使用範例

封裝元件 s-imgZoom.vue

<template>
    <div style="display: flex;">
        <div class="box"
             :style="minImgBoxStyle"
             @mouseleave="mouseLeave"
             @mouseenter="mouseEnter"
             @mousemove="mousemove($event)">
            <!--原始照片-小照片-->
            <img :style="minImgStyle" fit="contain" ref="minImg" :src="finalMinIMGsrc"/>
            <!--探測塊-->
            <div v-show="show" class="areaMark" :style="areaMarkStyle"></div>
        </div>
        <div class="box" :style="maxImgBoxStyle" v-show="show">
            <!--放大後的照片-->
            <img :style="maxImgStyle" fit="contain" :src="finalMaxIMGsrc"/>
        </div>
    </div>
</template>
<script>
    export default {
        props: {
            minIMGsrc: String,
            maxIMGsrc: String,
            scale: {
                type: Number,
                default: 2
            },
            width: {
                type: Number,
                default: 420
            },
            height: {
                type: Number,
                default: 420
            },
        },
        data() {
            return {
                show: false,
                finalMinIMGsrc: '',
                finalMaxIMGsrc: '',
                imgBoxWidth: 420,
                imgBoxHeight: 420,
                areaWidth: 210,
                areaHeight: 210,
                areaMarkStyle: {},
                minImgBoxStyle: {
                    cursor: 'move'
                },
                minImgStyle: {},
                maxImgBoxStyle: {},
                maxImgStyle: {
                    position: 'absolute',
                },
            }
        },
        mounted() {
            this.imgBoxWidth = this.width
            this.imgBoxHeight = this.height
            this.$set(this.minImgStyle, 'width', this.imgBoxWidth + 'px')
            this.$set(this.minImgStyle, 'height', this.imgBoxHeight + 'px')
            this.$set(this.maxImgStyle, 'width', this.imgBoxWidth + 'px')
            this.$set(this.maxImgStyle, 'height', this.imgBoxHeight + 'px')
            this.$set(this.minImgBoxStyle, 'width', this.imgBoxWidth + 'px')
            this.$set(this.minImgBoxStyle, 'height', this.imgBoxHeight + 'px')
            this.$set(this.maxImgBoxStyle, 'width', this.imgBoxWidth + 'px')
            this.$set(this.maxImgBoxStyle, 'height', this.imgBoxHeight + 'px')
            this.areaWidth = this.imgBoxWidth / this.scale
            this.areaHeight = this.imgBoxHeight / this.scale
            this.finalMinIMGsrc = this.minIMGsrc
            if (!this.maxIMGsrc) {
                this.finalMaxIMGsrc = this.minIMGsrc
            }
            this.$set(this.areaMarkStyle, 'width', this.areaWidth + 'px')
            this.$set(this.areaMarkStyle, 'height', this.areaHeight + 'px')
            this.$set(this.maxImgStyle, 'transform', 'scale(' + this.scale + ')')
        },
        methods: {
            mouseEnter() {
                this.show = true
            },
            mouseLeave() {
                this.show = false
            },
            mousemove(e) {
                // 獲取文件頂端與螢幕頂部之間的距離
                // scrollTop指的是“元素中的內容”超出“元素上邊界”的那部分的高度
                let documentScrollTop = document.documentElement.scrollTop || document.body.scrollTop;
                // 獲取滑鼠相對於螢幕的座標
                let mouseClientX = e.clientX
                let mouseClientY = e.clientY
                // 獲取小照片相對於螢幕位置資訊
                // getBoundingClientRect()用於獲得頁面中某個元素的左，上，右和下分別相對瀏覽器視窗的位置。
                let minImgPosition = this.$refs.minImg.getBoundingClientRect();
                let minImgX = minImgPosition.left;
                let minImgY = minImgPosition.top;
                // 計算出探測塊相對於小圖片的座標
                let areaLeft = mouseClientX - minImgX - this.areaWidth / 2
                let areaTop = mouseClientY - minImgY - this.areaHeight / 2
                if (documentScrollTop > 0) {
                    areaTop = documentScrollTop + areaTop
                }
                let minLeft = 0
                let maxLeft = this.imgBoxWidth - this.areaWidth
                let minTop = 0
                let maxTop = this.imgBoxHeight - this.areaHeight
                // 禁止探測塊移出小圖片
                if (areaLeft < minLeft) {
                    areaLeft = minLeft
                }
                if (areaLeft > maxLeft) {
                    areaLeft = maxLeft
                }
                if (areaTop < minTop) {
                    areaTop = minTop
                }
                if (areaTop > maxTop) {
                    areaTop = maxTop
                }
                // 更新探測塊的座標
                this.$set(this.areaMarkStyle, 'left', areaLeft + 'px')
                this.$set(this.areaMarkStyle, 'top', areaTop + 'px')
                // 更新放大後照片的座標
                this.$set(this.maxImgStyle, 'left', (this.scale - 1) * this.imgBoxWidth / 2 - areaLeft * this.scale + 'px')
                this.$set(this.maxImgStyle, 'top', (this.scale - 1) * this.imgBoxHeight / 2 - areaTop * this.scale + 'px')
            }
        }
    }
</script>
<style scoped>
    .box {
        border: 1px solid darkgray;
        position: relative;
        overflow: hidden;
        box-sizing: border-box;
    }

    .areaMark {
        position: absolute;
        background: url(//img-tmdetail.alicdn.com/tps/i4/T12pdtXaldXXXXXXXX-2-2.png);
    }
</style>
 

使用範例

<s-imgZoom  :width="300"  :height="300" minIMGsrc="https://img.alicdn.com/imgextra/i2/2183295419/O1CN01awKYlS1ptwv0tbmL5_!!0-item_pic.jpg_430x430q90.jpg" :scale="3" />