在 Vue 2 中实现 el-table 表头在浏览器滚动时吸顶效果

1. 全局注册自定义指令

首先，在 main.js 中全局注册一个自定义指令，用于处理表头的吸顶效果：

// main.js
import Vue from 'vue';
import App from './App.vue';
import router from './router';
import store from './store';

Vue.config.productionTip = false;
//自定义指令
Vue.directive('sticky', {
  inserted(el, binding) {
    const elTableHeader = el.querySelector('.el-table__header-wrapper');
    const stickyTop = binding.value || 0;

    const onScroll = () => {
      const scrollTop = window.scrollY || document.documentElement.scrollTop;
      const offsetTop = el.getBoundingClientRect().top + scrollTop;

      if (scrollTop > offsetTop) {
        elTableHeader.style.position = 'fixed';
        elTableHeader.style.top = stickyTop + 'px';
        elTableHeader.style.zIndex = 1000;
        elTableHeader.style.width = el.clientWidth + 'px'; // 防止表头宽度变化
      } else {
        elTableHeader.style.position = '';
        elTableHeader.style.top = '';
        elTableHeader.style.zIndex = '';
        elTableHeader.style.width = '';
      }
    };

    window.addEventListener('scroll', onScroll);

    el._onScroll = onScroll; // 保存引用以便在 unbind 钩子中移除事件监听
  },
  unbind(el) {
    window.removeEventListener('scroll', el._onScroll);
    delete el._onScroll;
  }
});

new Vue({
  router,
  store,
  render: h => h(App)
}).$mount('#app');

2. 组件中使用自定义指令

<div class="table-container" v-sticky="0">  //使用自定义指令
      <el-table :data="tableData" style="width: 100%" :header-cell-style="tableHeaderCellStyle" :cell-style="tableCellStyle" element-loading-spinner="el-icon-loading" v-loading="loading" >
        <el-table-column prop="date" label="达人" show-overflow-tooltip>
          <template slot-scope="scope">
            <div class="Expert_table_box">
              <div class="Expert_url" @click="Viewdetails(scope.row)">
                <el-image style="width: 0.8125rem; height: 0.8125rem; border-radius: 50%;" :key="scope.row.uid" :src="scope.row.avatar"></el-image>
              </div>
              <div class="Expert_table_detail">
                <span @click="Viewdetails(scope.row)" style="font-size: 0.1875rem; color: black">{{ scope.row.nickname }}</span>
                <span style="font-size: 0.15rem">{{ scope.row.douyinId }} &ensp;<i class="el-icon-copy-document" @click="copySpuId(scope.row.douyinId)"></i></span>
              </div>
            </div>
          </template>
        </el-table-column>
        <el-table-column prop="mplatformFollowersCount" label="粉丝数" sortable></el-table-column>
        <el-table-column prop="addFansCount" label="新增粉丝" sortable></el-table-column>
        <el-table-column prop="addAwemeCount" label="新增视频数" sortable></el-table-column>
        <el-table-column prop="awemeCount" label="视频总数" sortable></el-table-column>
        <el-table-column prop="totalFavorited" label="点赞数" sortable></el-table-column>
      </el-table>
    </div>