大致思路：
把所有选择的数据全部存到一个大数组中，切页的时候匹配原数据利用ref节点的.toggleRowSelection方法进行回显
具体步骤：
1、勾选和全选时需要判断是选中还是取消，然后更新大数组数据。
2、分页获取新数据之后匹配当前页应该选中的数据，使用 multipleTableRef.value!.toggleRowSelection(row, true);进行回显
所有代码：（示例为前端分页）
html
<template>
<div style="padding: 20px">
<el-table
ref="multipleTableRef"
:data="tableData"
@select-all="selectAllChange"
@select="handleSelectionChange"
>
<el-table-column type="selection" width="55" />
<el-table-column prop="username" label="用户名" show-overflow-tooltip />
<el-table-column prop="firstName" label="姓名" show-overflow-tooltip />
<el-table-column prop="email" label="邮箱" show-overflow-tooltip />
</el-table>
<!-- 分页器 -->
<div class="pagination">
<el-pagination
v-model:current-page="pagination.pageNum"
v-model:page-size="pagination.pageSize"
:page-sizes="[10, 20, 50, 100]"
layout="total, prev, pager, next,sizes, jumper"
:total="pagination.total"
@size-change="handleSizeChange"
@current-change="handleCurrentChange"
/>
</div>
<el-button type="primary" @click="yesTo">确 定</el-button>
</div>
</template>js
<script setup lang="ts">
import { ref, reactive, nextTick } from "vue";
import { ElMessage } from "element-plus";
import { setUsers } from "../../utils/api";
let listAll: any = []; // 存起来选中的数据
let multipleSelection: any = []; // 当前页选中的数据
const multipleTableRef = ref(); // 表格ref
let tableData = ref<any>([]); // 表格数据
let allList = reactive<any>([]);
//分页器
const pagination = reactive<any>({
pageNum: 1,
pageSize: 10,
total: 0,
});
// 前端分页-切割数据
const paging = () => {
// 起始位置 = (当前页 - 1) x 每页的大小
const start = (pagination.pageNum - 1) * pagination.pageSize;
// 结束位置 = 当前页 x 每页的大小
const end = pagination.pageNum * pagination.pageSize;
tableData.value = allList.slice(start, end);
};
// 获取列表数据
const getList = async () => {
// 接口请求
allList = [
{id:1, username: "admin1", firstName: "管理员", email: "123456@163.com" },
{id:2, username: "admin2", firstName: "管理员", email: "123456@163.com" },
{id:3, username: "admin3", firstName: "管理员", email: "123456@163.com" },
{id:4, username: "admin4", firstName: "管理员", email: "123456@163.com" },
{id:5, username: "admin5", firstName: "管理员", email: "123456@163.com" },
{id:6, username: "admin6", firstName: "管理员", email: "123456@163.com" },
{id:7, username: "admin7", firstName: "管理员", email: "123456@163.com" },
{id:8, username: "admin8", firstName: "管理员", email: "123456@163.com" },
{id:9, username: "admin9", firstName: "管理员", email: "123456@163.com" },
{id:10, username: "admin10", firstName: "管理员", email: "123456@163.com" },
{id:11, username: "admin11", firstName: "管理员", email: "123456@163.com" },
{id:12, username: "admin12", firstName: "管理员", email: "123456@163.com" },
{id:13, username: "admin13", firstName: "管理员", email: "123456@163.com" },
{id:14, username: "admin14", firstName: "管理员", email: "123456@163.com" },
{id:15, username: "admin15", firstName: "管理员", email: "123456@163.com" },
{id:16, username: "admin16", firstName: "管理员", email: "123456@163.com" },
{id:17, username: "admin17", firstName: "管理员", email: "123456@163.com" },
{id:18, username: "admin18", firstName: "管理员", email: "123456@163.com" },
];
pagination.total = allList.length;
paging();
toggleSelection(getTurn()); // 回显勾选
};
getList();
// 确认导入
const yesTo = async () => {
if (listAll.length) {
listAll = deduplicate(listAll, "username"); //去重
await setUsers(listAll);
ElMessage.success("导入成功");
getList();
} else {
ElMessage.warning("请先选择用户！");
}
};
// 匹配获取当前页应该选中的数据
const getTurn = () => {
let list: any = [];
listAll.forEach((v: any) => {
tableData.value.forEach((s: any) => {
if (v.username == s.username) list.push(s);
});
});
return list;
};
// 勾选时
const handleSelectionChange = (val: any, item: any) => {
multipleSelection = val;
listAll.push(...multipleSelection);
if (val.includes(item)) {
//勾选时做的事
} else {
//取消勾选时做的事，
listAll.forEach((v: any, i: number) => {
if (v.username == item.username) {
listAll.splice(i, 1);
}
});
}
};
// 全选
const selectAllChange = (val: any) => {
if (val.length) {
multipleSelection = JSON.parse(JSON.stringify(val));
listAll.push(...val);
} else {
multipleSelection.forEach((v: any) => {
listAll.forEach((s: any, i: number) => {
if (v.username == s.username) {
listAll.splice(i, 1);
}
});
});
multipleSelection = [];
}
};
// 当前页之前勾选过的数据 - 回显
const toggleSelection = (rows?: any) => {
nextTick(() => {
if (rows) {
rows.forEach((row: any) => {
multipleTableRef.value!.toggleRowSelection(row, true);
});
} else {
multipleTableRef.value!.clearSelection();
}
});
};
// 分页事件
const handleSizeChange = (val: number) => {
pagination.page = 1;
pagination.limit = val;
if (listAll.length) {
listAll = deduplicate(listAll, "username"); //去重
}
getList();
};
const handleCurrentChange = (val: number) => {
pagination.page = val;
if (listAll.length) {
listAll = deduplicate(listAll, "username"); //去重
}
getList();
};
// 数组去重方法
const deduplicate = (arr: any, t: any) => {
const newArr = [arr[0]];
for (let i = 1; i < arr.length; i++) {
let repeat = false;
for (let j = 0; j < newArr.length; j++) {
if (t && arr[i][t] === newArr[j][t]) {
repeat = true;
break;
}
}
if (!repeat) newArr.push(arr[i]);
}
return newArr;
};
</script>
