选中分页中不同的行

html中

1.     :row-key="getRowKeys"

2.    :reserve-selection="true"

<el-table :data="tableData" border stripe v-loading="loading" :row-key="getRowKeys" @selection-change="handleSelectionChangeUser" class="first-tab mt-10">
  <el-table-column type="selection" :reserve-selection="true" width="55" align="center"></el-table-column>
3.data中

data() {
  return {
    getRowKeys(row) {
      return row.id
    },
  }
}
4. methods中

handleSelectionChangeUser(val) {
  this.traineeData = val
}