element-plus侧边栏折叠

以下是使用element-plus实现侧边栏折叠的示例代码：

<template>
  <div class="container">
    <el-aside width="200px" style="background-color: rgb(238, 241, 246)">
      <el-menu default-active="1" class="el-menu-vertical-demo" :collapse="isCollapse">
        <el-submenu index="1">
          <template slot="title">
            <i class="el-icon-location"></i>
            <span>导航一</span>
          </template>
          <el-menu-item-group>
            <template slot="title">分组一</template>
            <el-menu-item index="1-1">选项1</el-menu-item>
            <el-menu-item index="1-2">选项2</el-menu-item>
          </el-menu-item-group>
          <el-menu-item-group title="分组2">
            <el-menu-item index="1-3">选项3</el-menu-item>
          </el-menu-item-group>
          <el-submenu index="1-4">
            <template slot="title">选项4</template>
            <el-menu-item index="1-4-1">选项4-1</el-menu-item>
          </el-submenu>
        </el-submenu>
        <el-menu-item index="2">
          <i class="el-icon-menu"></i>
          <span slot="title">导航二</span>
        </el-menu-item>
        <el-menu-item index="3">
          <i class="el-icon-setting"></i>
          <span slot="title">导航三</span>
        </el-menu-item>
      </el-menu>
    </el-aside>
    <el-main>
      <el-button type="primary" @click="toggleCollapse">{{isCollapse ? '展开' : '折叠'}}</el-button>
    </el-main>
  </div>
</template>

<script>
export default {
  data() {
    return {
      isCollapse: false
    }
  },
  methods: {
    toggleCollapse() {
      this.isCollapse = !this.isCollapse
    }
  }
}
</script>

<style>
.container {
  display: flex;
  height: 100vh;
}
.el-aside {
  height: 100%;
  overflow: hidden;
}
.el-menu-vertical-demo {
  height: 100%;
}
.el-main {
  flex: 1;
  padding: 20px;
}
</style>

在这个示例中，我们使用了`el-aside`和`el-menu`组件来实现侧边栏，其中`el-menu`组件的`collapse`属性用于控制菜单的折叠状态。我们通过点击按钮来切换`isCollapse`的值，从而实现侧边栏的折叠和展开。