关于手机端滚动加载更多多次触发事件问题

在做手机端滚动加载更多时,因为滚动是一个持续过程,所以就导致了会一次或很短时间内触发多次ajax请求,  可以设置一个全局变量控制.

// bool变量, 用于阻止滚动到底部连续触发多次

  let isBottom = true

const scrollHeight = element.currentTarget.scrollHeight
const scrollTop = element.currentTarget.scrollTop
// height - top - 容器高度
const scrollLength = scrollHeight - scrollTop
const liBottom = scrollLength - newsContainer
if (liBottom > 100 && liBottom < 180) {
  if (isBottom === true) {
    isBottom = false
    // $(ajax)
  }
}

然后取消false,百度很多都是设置延迟1秒种取消,我是用的滚动条高度

if (liBottom > 1000) {
      isBottom = true
    }

  // 视频模板
  const vTemple = (url, title, image, visit, catName) => {
    const res = `

    

    
${title}
    
    

    
    
    

    
    
    

      
        
      
    
    
阅读量：${visit}    ${catName}
    
`
    return res
  }
  // 无内容
  const noTemple = () => {
    const res = '
再怎么拉都没有啦，不如看看其他版块内容吧！
'
    return res
  }
  // 分页
  let currentPage = 1
  // 分类id
  let categoryId = 0
  // 用户id
  let userId = 0
  // bool变量, 用于阻止滚动到底部连续触发多次
  let isBottom = true
  const windowHeight = $(window).height()
  // 列表容器高度
  const newsContainer = windowHeight - 120
  // 设置容器高度
  $('.mobile-main .m-news-list-tit').css('height', `${newsContainer}px`)
  // 滚动监听
  $('.mobile-main .m-news-list-tit').on('scroll', (element) => {
    const scrollHeight = element.currentTarget.scrollHeight
    const scrollTop = element.currentTarget.scrollTop
    // height - top - 容器高度
    const scrollLength = scrollHeight - scrollTop
    const liBottom = scrollLength - newsContainer
    if (liBottom > 100 && liBottom < 250) {
      if (isBottom === true) {
        // isBottom 为false 防止连续下拉加载多次
        isBottom = false
        categoryId = $(element.currentTarget).find('#categoryId').val()
        userId = $(element.currentTarget).find('#userId').val()
        const nextPage = currentPage + 1
        const ajaxOptions = {
          method: 'POST',
          data: {
            id: categoryId,
            user_id: userId,
            page: nextPage
          }
        }
        let articleList = ''
        $.ajax('xxxxxx', ajaxOptions).done((data) => {
          const articles = data.articles
          articles.forEach((article) => {
            let url = article.url
            if (article.url === '') {
              url = `/articles/${article.id}`
            }
            const title = article.title
            let image = article.image 
            const visit = article.visit
            const catName = article.name
            articleList = vTemple(url, title, image, visit, catName)
            $(element.currentTarget).find('.articles-list-summary').append(articleList)
          })
          if (articles.length > 0 && articles.length < 19) {
            articleList = noTemple()
            $(element.currentTarget).find('.articles-list-summary').append(articleList)
          }
        }).fail(() => {
          // no data
        })
        // 下一页
        currentPage = nextPage
      }
    }
    // 当滚动条高度变化后让isBottom为true
    if (liBottom > 1000) {
      isBottom = true
    }
  })