vue3 element el-table表头冻结，表头吸顶directives方法

1、在文件夹中创建directives文件

/**
 * 思路:通过简体 el-table的 thead和tbody父级别区域，进行设置对于的fixed
 */

function getElParentBySelector(el, queryClassSelector) {
    if (!el) {
      return el
    }
    if ([...el.classList].includes(queryClassSelector)) {
      return el
    }
    return getElParentBySelector(el.parentNode, queryClassSelector)
  }
  
  function getTableShowWidth(thead) {
    const tableBox = getElParentBySelector(thead, 'el-table')
    return tableBox.getBoundingClientRect().width
  }
  
  function createTableSticky(el, binding) {
    // 获取表格(element)
    console.log(el,99937)
    let thead = el.querySelector('.el-table__header')
    thead = getElParentBySelector(thead, 'el-table__header-wrapper')
    const tbody = el.querySelector('.el-table__body')
  
    //获取thead 的显示宽度
    const headerShowWidth = getTableShowWidth(thead)
  
    // 获取滚动元素
    const scrollParent = document.querySelector(binding.value.parent||'body')
    console.log(scrollParent,binding.value.disabled,88882)
    if (!scrollParent || binding.value.disabled === true) {
      return
    }
    scrollParent.addEventListener('scroll', function () {
        const stickyTop= binding.value.top||0;
      const theadHeight = thead.clientHeight
      // 获取thead距离顶部的距离
      const theadTop = thead.getBoundingClientRect().top
      console.log(theadTop,theadHeight,"theadToptheadTop")
      if (theadTop <= stickyTop) {
        tbody.style.paddingTop = theadHeight + 'px'
        thead.style.position = 'fixed'
        thead.style.zIndex = '2021'
        thead.style.top = stickyTop + 'px'
        thead.style.borderTop = '1px solid #EBEBEB'
  
        //thead.style.width = tbody.offsetWidth + 'px' //
  
        //使用最佳显示宽度显示内容，防止有横向滚动条时，固定列显示超出
         thead.style.width =
          (tbody.offsetWidth < headerShowWidth ? tbody.offsetWidth : headerShowWidth) + 'px'
        
  
        //获取父级别的宽度，设置列头行只能是负极宽度
      }
      // 判断是否需要回归原来位置
      const originally = tbody.getBoundingClientRect().top
      // 判断底部距离是否超过表头
      const goBeyond = tbody.getBoundingClientRect().bottom
      if (originally > stickyTop || goBeyond <= thead.offsetHeight) {
        tbody.style.paddingTop = '0'
        thead.style.position = 'relative'
        thead.style.zIndex = '0'
        thead.style.top = 0 + 'px'
        thead.style.width = tbody.offsetWidth + 'px' //固定表头有bug的话改成 auto
        thead.style.borderTop = 'none'
      }
    })
  }
  
  var clearTimeId = 0;
  const createSticky = {
    mounted(el, binding) {
    //TIP 延时设置，确保表格进行渲染成功！
    // el.addEventListener("scroll", createTableSticky(el, binding));
        clearTimeId = setTimeout(() => {
            createTableSticky(el, binding)
            clearTimeout(clearTimeId)
        }, 1000)
    },
    unmounted(el, binding) {
    clearTimeId && clearTimeout(clearTimeId)
    }
  }
  export default createSticky

2、在main中引用全局

const app = createApp(App);
import createSticky from './directives/sticky'
app.directive('sticky',createSticky)
app.mount("#app");

3、使用:

v-sticky="{ top: 185, parent: '.page_main' }"

注意：table不要加高度，数据少于高度列时会在数据最后一列那消失
page_main是指有滚轮的父级页面

参考：

https://blog.csdn.net/qq_28254093/article/details/134642885