子元素滚，父元素不滚

scrollUnique.js

$.fn.scrollUnique = function() {
  return $(this).each(function() {
    let eventType = 'mousewheel'
    // 火狐是DOMMouseScroll事件
    if (navigator.userAgent.indexOf('Firefox') > -1) {
      eventType = 'DOMMouseScroll'
    }
    $(this).on(eventType, function(event) {
      // 一些数据
      let scrollTop = this.scrollTop,
        scrollHeight = this.scrollHeight,
        height = this.clientHeight

      let delta = event.originalEvent.wheelDelta
        ? event.originalEvent.wheelDelta
        : -(event.originalEvent.detail || 0)

      if (
        (delta > 0 && scrollTop <= delta) ||
        (delta < 0 && scrollHeight - height - scrollTop <= -1 * delta)
      ) {
        // IE浏览器下滚动会跨越边界直接影响父级滚动，因此，临界时候手动边界滚动定位
        this.scrollTop = delta > 0 ? 0 : scrollHeight
        // 向上滚 || 向下滚
        let event = window.event || event
        if (event.stopPropagation) {
          event.stopPropagation()
        } else {
          event.cancelBubble = true
        }
        if (event.preventDefault) {
          event.preventDefault()
        } else {
          event.returnValue = false
        }
      }
    })
  })
}