JavaScript 中 onwheel 鼠標滾輪事件wheelDelta 和 deltaY

 

<style>
    .da-fei {
        width: 800px;
        height: 800px;
        background-color: #c0c0c0;
    }
</style>
<div class="da-fei" onwheel="setZoom()"></div>

<script>
    function setZoom() {
        console.log(event);
        let eventDelta = event.wheelDelta || -event.deltaY + 40;// 火狐和其他瀏覽器都兼容
        console.log(eventDelta) ;// 
        let zoomSize = eventDelta / 120; // 如果是正數向上,復數向下
    }
</script>

 其他

wheel_event