vue3 之商城项目

购物车业务逻辑梳理拆解

1️⃣整个购物车的实现分为两个大分支，本地购物车操作和接口购物车操作
2️⃣由于购物车数据的特殊性，采取Pinia管理购物车列表数据并添加持久话缓存
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本地购物车—加入购物车实现

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stores/cartStore.js

// 封装购物车模块
import { defineStore } from 'pinia'
import { ref } from 'vue'
export const useCartStore = defineStore('cart', () => {
  // 1. 定义state - cartList
  const cartList = ref([])
  // 2. 定义action - addCart
  const addCart = (goods) => {
    console.log('添加', goods)
    // 添加购物车操作
    // 已添加过 - count + 1
    // 没有添加过 - 直接push
    // 思路：通过匹配传递过来的商品对象中的skuId能不能在cartList中找到，找到了就是添加过
    const item = cartList.value.find((item) => goods.skuId === item.skuId)
    if (item) {
      // 找到了
      item.count++
    } else {
      // 没找到
      cartList.value.push(goods)
    }
  }
  return {
    cartList,
    addCart
  }
}, {
  persist: true,
})

detail/index.vue

<script setup>
import DetailHot from './components/DetailHot.vue'
import { getDetail } from '@/apis/detail'
import { onMounted, ref } from 'vue'
import { useRoute } from 'vue-router'
import { ElMessage } from 'element-plus'
import { useCartStore } from '@/stores/cartStore'
const cartStore = useCartStore()
const goods = ref({})
const route = useRoute()
const getGoods = async () => {
  const res = await getDetail(route.params.id)
  goods.value = res.result
}
onMounted(() => getGoods())

// sku规格被操作时
let skuObj = {}
const skuChange = (sku) => {
  console.log(sku)
  skuObj = sku
}

// count
const count = ref(1)
const countChange = (count) => {
  console.log(count)
}

// 添加购物车
const addCart = () => {
  if (skuObj.skuId) {
    console.log(skuObj, cartStore.addCart)
    // 规则已经选择  触发action
    cartStore.addCart({
      id: goods.value.id,
      name: goods.value.name,
      picture: goods.value.mainPictures[0],
      price: goods.value.price,
      count: count.value,
      skuId: skuObj.skuId,
      attrsText: skuObj.specsText,
      selected: true
    })
  } else {
    // 规格没有选择 提示用户
    ElMessage.warning('请选择规格')
  }
}

</script>

<template>
  <div class="xtx-goods-page">
    <div class="container" v-if="goods.details">
      <div class="bread-container">
        <el-breadcrumb separator=">">
          <el-breadcrumb-item :to="{ path: '/' }">首页</el-breadcrumb-item>
          <el-breadcrumb-item :to="{ path: `/category/${goods.categories[1].id}` }">{{ goods.categories[1].name }}
          </el-breadcrumb-item>
          <el-breadcrumb-item :to="{ path: `/category/sub/${goods.categories[0].id}` }">{{
            goods.categories[0].name
          }}
          </el-breadcrumb-item>
          <el-breadcrumb-item>抓绒保暖，毛毛虫子儿童运动鞋</el-breadcrumb-item>
        </el-breadcrumb>
      </div>
      <!-- 商品信息 -->
      <div class="info-container">
        <div>
          <div class="goods-info">
            <div class="media">
              <!-- 图片预览区 -->
              <XtxImageView :image-list="goods.mainPictures" />
              <!-- 统计数量 -->
              <ul class="goods-sales">
                <li>
                  <p>销量人气</p>
                  <p> {{ goods.salesCount }}+ </p>
                  <p><i class="iconfont icon-task-filling"></i>销量人气</p>
                </li>
                <li>
                  <p>商品评价</p>
                  <p>{{ goods.commentCount }}+</p>
                  <p><i class="iconfont icon-comment-filling"></i>查看评价</p>
                </li>
                <li>
                  <p>收藏人气</p>
                  <p>{{ goods.collectCount }}+</p>
                  <p><i class="iconfont icon-favorite-filling"></i>收藏商品</p>
                </li>
                <li>
                  <p>品牌信息</p>
                  <p>{{ goods.brand.name }}</p>
                  <p><i class="iconfont icon-dynamic-filling"></i>品牌主页</p>
                </li>
              </ul>
            </div>
            <div class="spec">
              <!-- 商品信息区 -->
              <p class="g-name"> {{ goods.name }} </p>
              <p class="g-desc">{{ goods.desc }} </p>
              <p class="g-price">
                <span>{{ goods.oldPrice }}</span>
                <span> {{ goods.price }}</span>
              </p>
              <div class="g-service">
                <dl>
                  <dt>促销</dt>
                  <dd>12月好物放送，App领券购买直降120元</dd>
                </dl>
                <dl>
                  <dt>服务</dt>
                  <dd>
                    <span>无忧退货</span>
                    <span>快速退款</span>
                    <span>免费包邮</span>
                    <a href="javascript:;">了解详情</a>
                  </dd>
                </dl>
              </div>
              <!-- sku组件 -->
              <XtxSku :goods="goods" @change="skuChange" />
              <!-- 数据组件 -->
              <el-input-number v-model="count" @change="countChange" />
              <!-- 按钮组件 -->
              <div>
                <el-button size="large" class="btn" @click="addCart">
                  加入购物车
                </el-button>
              </div>

            </div>
          </div>
          <div class="goods-footer">
            <div class="goods-article">
              <!-- 商品详情 -->
              <div class="goods-tabs">
                <nav>
                  <a>商品详情</a>
                </nav>
                <div class="goods-detail">
                  <!-- 属性 -->
                  <ul class="attrs">
                    <li v-for="item in goods.details.properties" :key="item.value">
                      <span class="dt">{{ item.name }}</span>
                      <span class="dd">{{ item.value }}</span>
                    </li>
                  </ul>
                  <!-- 图片 -->
                  <img v-for="img in goods.details.pictures" :src="img" :key="img" alt="">
                </div>
              </div>
            </div>
            <!-- 24热榜+专题推荐 -->
            <div class="goods-aside">
              <!-- 24小时 -->
              <DetailHot :hot-type="1" />
              <!-- 周 -->
              <DetailHot :hot-type="2" />
            </div>
          </div>
        </div>
      </div>
    </div>
  </div>
</template>


<style scoped lang='scss'>
.xtx-goods-page {
  .goods-info {
    min-height: 600px;
    background: #fff;
    display: flex;

    .media {
      width: 580px;
      height: 600px;
      padding: 30px 50px;
    }

    .spec {
      flex: 1;
      padding: 30px 30px 30px 0;
    }
  }

  .goods-footer {
    display: flex;
    margin-top: 20px;

    .goods-article {
      width: 940px;
      margin-right: 20px;
    }

    .goods-aside {
      width: 280px;
      min-height: 1000px;
    }
  }

  .goods-tabs {
    min-height: 600px;
    background: #fff;
  }

  .goods-warn {
    min-height: 600px;
    background: #fff;
    margin-top: 20px;
  }

  .number-box {
    display: flex;
    align-items: center;

    .label {
      width: 60px;
      color: #999;
      padding-left: 10px;
    }
  }

  .g-name {
    font-size: 22px;
  }

  .g-desc {
    color: #999;
    margin-top: 10px;
  }

  .g-price {
    margin-top: 10px;

    span {
      &::before {
        content: "¥";
        font-size: 14px;
      }

      &:first-child {
        color: $priceColor;
        margin-right: 10px;
        font-size: 22px;
      }

      &:last-child {
        color: #999;
        text-decoration: line-through;
        font-size: 16px;
      }
    }
  }

  .g-service {
    background: #f5f5f5;
    width: 500px;
    padding: 20px 10px 0 10px;
    margin-top: 10px;

    dl {
      padding-bottom: 20px;
      display: flex;
      align-items: center;

      dt {
        width: 50px;
        color: #999;
      }

      dd {
        color: #666;

        &:last-child {
          span {
            margin-right: 10px;

            &::before {
              content: "•";
              color: $xtxColor;
              margin-right: 2px;
            }
          }

          a {
            color: $xtxColor;
          }
        }
      }
    }
  }

  .goods-sales {
    display: flex;
    width: 400px;
    align-items: center;
    text-align: center;
    height: 140px;

    li {
      flex: 1;
      position: relative;

      ~li::after {
        position: absolute;
        top: 10px;
        left: 0;
        height: 60px;
        border-left: 1px solid #e4e4e4;
        content: "";
      }

      p {
        &:first-child {
          color: #999;
        }

        &:nth-child(2) {
          color: $priceColor;
          margin-top: 10px;
        }

        &:last-child {
          color: #666;
          margin-top: 10px;

          i {
            color: $xtxColor;
            font-size: 14px;
            margin-right: 2px;
          }

          &:hover {
            color: $xtxColor;
            cursor: pointer;
          }
        }
      }
    }
  }
}

.goods-tabs {
  min-height: 600px;
  background: #fff;

  nav {
    height: 70px;
    line-height: 70px;
    display: flex;
    border-bottom: 1px solid #f5f5f5;

    a {
      padding: 0 40px;
      font-size: 18px;
      position: relative;

      >span {
        color: $priceColor;
        font-size: 16px;
        margin-left: 10px;
      }
    }
  }
}

.goods-detail {
  padding: 40px;

  .attrs {
    display: flex;
    flex-wrap: wrap;
    margin-bottom: 30px;

    li {
      display: flex;
      margin-bottom: 10px;
      width: 50%;

      .dt {
        width: 100px;
        color: #999;
      }

      .dd {
        flex: 1;
        color: #666;
      }
    }
  }

  >img {
    width: 100%;
  }
}

.btn {
  margin-top: 20px;

}

.bread-container {
  padding: 25px 0;
}
</style>

本地购物车—头部购物车列表渲染

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HeaderCart.vue

<script setup>
import { useCartStore } from '@/stores/cartStore'
const cartStore = useCartStore()
</script>
<template>
  <div class="cart">
    <a class="curr" href="javascript:;">
      <i class="iconfont icon-cart"></i><em>{{ cartStore.cartList.length }}</em>
    </a>
    <div class="layer">
      <div class="list">

        <div class="item" v-for="i in cartStore.cartList" :key="i">
          <RouterLink to="">
            <img :src="i.picture" alt="" />
            <div class="center">
              <p class="name ellipsis-2">
                {{ i.name }}
              </p>
              <p class="attr ellipsis">{{ i.attrsText }}</p>
            </div>
            <div class="right">
              <p class="price">&yen;{{ i.price }}</p>
              <p class="count">x{{ i.count }}</p>
            </div>
          </RouterLink>
          <i class="iconfont icon-close-new" @click="cartStore.delCart(i.skuId)"></i>
        </div>

      </div>
      <div class="foot">
        <div class="total">
          <p>共 {{ cartStore.allCount }} 件商品</p>
          <p>&yen; {{ cartStore.allPrice.toFixed(2) }} </p>
        </div>
        <el-button size="large" type="primary" @click="$router.push('/cartlist')">去购物车结算</el-button>
      </div>
    </div>
</div>
</template>

<style scoped lang="scss">
.cart {
  width: 50px;
  position: relative;
  z-index: 600;

  .curr {
    height: 32px;
    line-height: 32px;
    text-align: center;
    position: relative;
    display: block;

    .icon-cart {
      font-size: 22px;
    }

    em {
      font-style: normal;
      position: absolute;
      right: 0;
      top: 0;
      padding: 1px 6px;
      line-height: 1;
      background: $helpColor;
      color: #fff;
      font-size: 12px;
      border-radius: 10px;
      font-family: Arial;
    }
  }

  &:hover {
    .layer {
      opacity: 1;
      transform: none;
    }
  }

  .layer {
    opacity: 0;
    transition: all 0.4s 0.2s;
    transform: translateY(-200px) scale(1, 0);
    width: 400px;
    height: 400px;
    position: absolute;
    top: 50px;
    right: 0;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.2);
    background: #fff;
    border-radius: 4px;
    padding-top: 10px;

    &::before {
      content: "";
      position: absolute;
      right: 14px;
      top: -10px;
      width: 20px;
      height: 20px;
      background: #fff;
      transform: scale(0.6, 1) rotate(45deg);
      box-shadow: -3px -3px 5px rgba(0, 0, 0, 0.1);
    }

    .foot {
      position: absolute;
      left: 0;
      bottom: 0;
      height: 70px;
      width: 100%;
      padding: 10px;
      display: flex;
      justify-content: space-between;
      background: #f8f8f8;
      align-items: center;

      .total {
        padding-left: 10px;
        color: #999;

        p {
          &:last-child {
            font-size: 18px;
            color: $priceColor;
          }
        }
      }
    }
  }

  .list {
    height: 310px;
    overflow: auto;
    padding: 0 10px;

    &::-webkit-scrollbar {
      width: 10px;
      height: 10px;
    }

    &::-webkit-scrollbar-track {
      background: #f8f8f8;
      border-radius: 2px;
    }

    &::-webkit-scrollbar-thumb {
      background: #eee;
      border-radius: 10px;
    }

    &::-webkit-scrollbar-thumb:hover {
      background: #ccc;
    }

    .item {
      border-bottom: 1px solid #f5f5f5;
      padding: 10px 0;
      position: relative;

      i {
        position: absolute;
        bottom: 38px;
        right: 0;
        opacity: 0;
        color: #666;
        transition: all 0.5s;
      }

      &:hover {
        i {
          opacity: 1;
          cursor: pointer;
        }
      }

      a {
        display: flex;
        align-items: center;

        img {
          height: 80px;
          width: 80px;
        }

        .center {
          padding: 0 10px;
          width: 200px;

          .name {
            font-size: 16px;
          }

          .attr {
            color: #999;
            padding-top: 5px;
          }
        }

        .right {
          width: 100px;
          padding-right: 20px;
          text-align: center;

          .price {
            font-size: 16px;
            color: $priceColor;
          }

          .count {
            color: #999;
            margin-top: 5px;
            font-size: 16px;
          }
        }
      }
    }
  }
}
</style>

本地购物车—头部购物车删除实现

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stores/cartStore.js

 // 删除购物车
  const delCart = async (skuId) => {
      // 思路：
      // 1. 找到要删除项的下标值 - splice
      // 2. 使用数组的过滤方法 - filter
      const idx = cartList.value.findIndex((item) => skuId === item.skuId)
      cartList.value.splice(idx, 1)
  }

HeaderCart.vue

  <i class="iconfont icon-close-new" @click="cartStore.delCart(i.skuId)"></i>

本地购物车—头部购物车统计计算

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计算逻辑
1️⃣商品总数计算逻辑：商品列表中的所有商品count累加之和
2️⃣商品总价钱计算逻辑：商品列表中的所有商品的count*price累加之和
stores/cartStore.js

  // 计算属性
  // 1. 总的数量 所有项的count之和
  const allCount = computed(() => cartList.value.reduce((a, c) => a + c.count, 0))
  // 2. 总价 所有项的count*price之和
  const allPrice = computed(() => cartList.value.reduce((a, c) => a + c.count * c.price, 0))

本地购物车—列表购物车

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cartList/index.vue

<script setup>
import { useCartStore } from '@/stores/cartStore'
const cartStore = useCartStore()

</script>

<template>
  <div class="xtx-cart-page">
    <div class="container m-top-20">
      <div class="cart">
        <table>
          <thead>
            <tr>
              <th width="120">
                <el-checkbox :model-value="cartStore.isAll" @change="allCheck" />
              </th>
              <th width="400">商品信息</th>
              <th width="220">单价</th>
              <th width="180">数量</th>
              <th width="180">小计</th>
              <th width="140">操作</th>
            </tr>
          </thead>
          <!-- 商品列表 -->
          <tbody>
            <tr v-for="i in cartStore.cartList" :key="i.id">
              <td>
                <!-- 单选框 -->
                <el-checkbox :model-value="i.selected" @change="(selected) => singleCheck(i, selected)" />
              </td>
              <td>
                <div class="goods">
                  <RouterLink to="/"><img :src="i.picture" alt="" /></RouterLink>
                  <div>
                    <p class="name ellipsis">
                      {{ i.name }}
                    </p>
                  </div>
                </div>
              </td>
              <td class="tc">
                <p>&yen;{{ i.price }}</p>
              </td>
              <td class="tc">
                <el-input-number v-model="i.count" />
              </td>
              <td class="tc">
                <p class="f16 red">&yen;{{ (i.price * i.count).toFixed(2) }}</p>
              </td>
              <td class="tc">
                <p>
                  <el-popconfirm title="确认删除吗?" confirm-button-text="确认" cancel-button-text="取消" @confirm="delCart(i)">
                    <template #reference>
                      <a href="javascript:;">删除</a>
                    </template>
                  </el-popconfirm>
                </p>
              </td>
            </tr>
            <tr v-if="cartStore.cartList.length === 0">
              <td colspan="6">
                <div class="cart-none">
                  <el-empty description="购物车列表为空">
                    <el-button type="primary">随便逛逛</el-button>
                  </el-empty>
                </div>
              </td>
            </tr>
          </tbody>

        </table>
      </div>
      <!-- 操作栏 -->
      <div class="action">
        <div class="batch">
          共 {{ cartStore.allCount }} 件商品，已选择 {{ cartStore.selectedCount }} 件，商品合计：
          <span class="red">¥ {{ cartStore.selectedPrice.toFixed(2) }} </span>
        </div>
        <div class="total">
          <el-button size="large" type="primary" @click="$router.push('/checkout')">下单结算</el-button>
        </div>
      </div>
    </div>
  </div>
</template>

<style scoped lang="scss">
.xtx-cart-page {
  margin-top: 20px;

  .cart {
    background: #fff;
    color: #666;

    table {
      border-spacing: 0;
      border-collapse: collapse;
      line-height: 24px;

      th,
      td {
        padding: 10px;
        border-bottom: 1px solid #f5f5f5;

        &:first-child {
          text-align: left;
          padding-left: 30px;
          color: #999;
        }
      }

      th {
        font-size: 16px;
        font-weight: normal;
        line-height: 50px;
      }
    }
  }

  .cart-none {
    text-align: center;
    padding: 120px 0;
    background: #fff;

    p {
      color: #999;
      padding: 20px 0;
    }
  }

  .tc {
    text-align: center;

    a {
      color: $xtxColor;
    }

    .xtx-numbox {
      margin: 0 auto;
      width: 120px;
    }
  }

  .red {
    color: $priceColor;
  }

  .green {
    color: $xtxColor;
  }

  .f16 {
    font-size: 16px;
  }

  .goods {
    display: flex;
    align-items: center;

    img {
      width: 100px;
      height: 100px;
    }

    >div {
      width: 280px;
      font-size: 16px;
      padding-left: 10px;

      .attr {
        font-size: 14px;
        color: #999;
      }
    }
  }

  .action {
    display: flex;
    background: #fff;
    margin-top: 20px;
    height: 80px;
    align-items: center;
    font-size: 16px;
    justify-content: space-between;
    padding: 0 30px;

    .xtx-checkbox {
      color: #999;
    }

    .batch {
      a {
        margin-left: 20px;
      }
    }

    .red {
      font-size: 18px;
      margin-right: 20px;
      font-weight: bold;
    }
  }

  .tit {
    color: #666;
    font-size: 16px;
    font-weight: normal;
    line-height: 50px;
  }

}
</style>

router.js

// createRouter：创建router实例对象
// createWebHistory：创建history模式的路由
import { createRouter, createWebHistory } from 'vue-router'
import Login from '@/views/Login/index.vue'
import Layout from '@/views/Layout/index.vue'
import Home from '@/views/Home/index.vue'
import Category from '@/views/Category/index.vue'
import SubCategory from '@/views/SubCategory/index.vue'
import Detail from '@/views/Detail/index.vue'
import CartList from '@/views/CartList/index.vue'

const router = createRouter({
  history: createWebHistory(import.meta.env.BASE_URL),
  // path和component对应关系的位置
  routes: [
    {
      path: '/',
      component: Layout,
      children: [
        {
          path: '',
          component: Home
        },
        {
          path: 'category/:id',
          component: Category
        },
        {
          path: 'category/sub/:id',
          component: SubCategory
        },
        {
          path: 'detail/:id',
          component: Detail
        },
        {
          path: 'cartlist',
          component: CartList
        }
      ]
    },
    {
      path: '/login',
      component: Login
    }
  ],
  // 路由滚动行为定制
  scrollBehavior () {
    return {
      top: 0
    }
  }
})

export default router

列表购物车—单选功能

核心思路
单选的核心思路就是始终把单选框的状态和Pinia中的store对应的状态保持同步
注意事项
v-model双向绑定指令不方便进行命令式的操作（因为后续还需要调用接口），所以把v-model回退到一般模式，也就是model-value和@change的配合实现
在这里插入图片描述

cartStore.js

const singleCheck = (skuId, selected) => {
  // 通过skuId找到要修改的那一项 然后把它的selected修改为传过来的selected
  const item = cartList.value.find((item) => item.skuId === skuId)
  item.selected = selected
}

cartList/index.vue

// 单选回调
const singleCheck = (i, selected) => {
  console.log(i, selected)
  // store cartList 数组 无法知道要修改谁的选中状态？
  // 除了selected补充一个用来筛选的参数 - skuId
  cartStore.singleCheck(i.skuId, selected)
}
<template>
  <td>
    <!-- 单选框 -->
    <el-checkbox :model-value="i.selected" @change="(selected) => singleCheck(i, selected)" />
  </td>
</template>

列表购物车—全选

核心思路
1️⃣操作单选决定全选：只有当cartList中的所有项都为true时，全选状态才为true
2️⃣操作全选决定单选：cartList中的所有项的selected都要跟着一起变
在这里插入图片描述
cartStore.js

  // 全选功能
  const allCheck = (selected) => {
    // 把cartList中的每一项的selected都设置为当前的全选框状态
    cartList.value.forEach(item => item.selected = selected)
  }
  // 是否全选
  const isAll = computed(() => cartList.value.every((item) => item.selected))

cartList/index.vue

const allCheck = (selected) => {
  cartStore.allCheck(selected)
}
 <el-checkbox :model-value="cartStore.isAll" @change="allCheck" />

列表购物车—统计数据实现

在这里插入图片描述
计算逻辑
1️⃣已选择数量=cartList中所有selected字段为true项的count之和
2️⃣商品合计=cartList中所有selected字段为true项的count*price之和

cartStore.js

// 3. 已选择数量
  const selectedCount = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count, 0))
  // 4. 已选择商品价钱合计
  const selectedPrice = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count * c.price, 0))

cartList/index.vue

 <!-- 操作栏 -->
      <div class="action">
        <div class="batch">
          共 {{ cartStore.allCount }} 件商品，已选择 {{ cartStore.selectedCount }} 件，商品合计：
          <span class="red">¥ {{ cartStore.selectedPrice.toFixed(2) }} </span>
        </div>
        <div class="total">
          <el-button size="large" type="primary" @click="$router.push('/checkout')">下单结算</el-button>
        </div>
      </div>

接口购物车—加入购物车

在这里插入图片描述
结论
到目前为止，购物车在非登陆状态下的各种操作都已经ok了，包括action的封装，触发，参数传递，剩下的事情就是action中做登录状态的分支判断，补充登录状态下的接口操作逻辑即可

cartStore.js

import { defineStore } from 'pinia'
import { useUserStore } from './userStore'
import { computed, ref } from 'vue'
import { insertCartAPI, findNewCartListAPI, delCartAPI  } from '@/apis/cart'
export const useCartStore = defineStore('cart', () => {
  const userStore = useUserStore()
   // 1. 定义state - cartList
  const cartList = ref([])
  const isLogin = computed(() => userStore.userInfo.token)
  // 获取最新购物车列表action
  const updateNewList = async () => {
    const res = await findNewCartListAPI()
    cartList.value = res.result
  }
  const addCart = async (goods) => {
    const { skuId, count } = goods
    // 登录
    if (isLogin.value) {
      // 登录之后的加入购车逻辑
      await insertCartAPI({ skuId, count })
      updateNewList()
    } else {
      // 未登录
      const item = cartList.value.find((item) => goods.skuId === item.skuId)
      if (item) {
        // 找到了
        item.count++
      } else {
        // 没找到
        cartList.value.push(goods)
      }
    }
  }
}, {
  persist: true,
})

接口购物车—删除购物车

在这里插入图片描述
cartStore.js

 // 删除购物车
  const delCart = async (skuId) => {
    if (isLogin.value) {
      // 调用接口实现接口购物车中的删除功能
      await delCartAPI([skuId])
      updateNewList()
    } else {
      // 思路：
      // 1. 找到要删除项的下标值 - splice
      // 2. 使用数组的过滤方法 - filter
      const idx = cartList.value.findIndex((item) => skuId === item.skuId)
      cartList.value.splice(idx, 1)
    }
  }

退出登陆—清空购物车列表

业务需求
在用户退出登陆时，清除用户信息同时也要把购物车数据清空
在这里插入图片描述
cartStore.js

 // 清除购物车
  const clearCart = () => {
    cartList.value = []
  }

userStore.js

  import { useCartStore } from './cartStore'
  const cartStore = useCartStore()
  // 退出时清除用户信息
  const clearUserInfo = () => {
    userInfo.value = {}
    // 执行清除购物车的action
    cartStore.clearCart()
  }

合并本地购物车到服务器

用户在非登陆时所进行的操作，登陆后把本地的购物车数据和服务端购物车数据进行合并
在这里插入图片描述
实现步骤

userStore.js

 // 2. 定义获取接口数据的action函数
  const getUserInfo = async ({ account, password }) => {
    const res = await loginAPI({ account, password })
    userInfo.value = res.result
    // 合并购物车的操作
    await mergeCartAPI(cartStore.cartList.map(item => {
      return {
        skuId: item.skuId,
        selected: item.selected,
        count: item.count
      }
    }))
    cartStore.updateNewList()
  }

完整代码

userStore.js

// 管理用户数据相关
import { defineStore } from 'pinia'
import { ref } from 'vue'
import { loginAPI } from '@/apis/user'
import { useCartStore } from './cartStore'
import { mergeCartAPI } from '@/apis/cart'
export const useUserStore = defineStore('user', () => {
  const cartStore = useCartStore()
  // 1. 定义管理用户数据的state
  const userInfo = ref({})
  // 2. 定义获取接口数据的action函数
  const getUserInfo = async ({ account, password }) => {
    const res = await loginAPI({ account, password })
    userInfo.value = res.result
    // 合并购物车的操作
    await mergeCartAPI(cartStore.cartList.map(item => {
      return {
        skuId: item.skuId,
        selected: item.selected,
        count: item.count
      }
    }))
    cartStore.updateNewList()
  }

  // 退出时清除用户信息
  const clearUserInfo = () => {
    userInfo.value = {}
    // 执行清除购物车的action
    cartStore.clearCart()
  }
  // 3. 以对象的格式把state和action return
  return {
    userInfo,
    getUserInfo,
    clearUserInfo
  }
}, {
  persist: true,
})

cartStore.js

// 封装购物车模块

import { defineStore } from 'pinia'
import { computed, ref } from 'vue'
import { useUserStore } from './userStore'
import { insertCartAPI, findNewCartListAPI, delCartAPI } from '@/apis/cart'
export const useCartStore = defineStore('cart', () => {
  const userStore = useUserStore()
  const isLogin = computed(() => userStore.userInfo.token)
  // 1. 定义state - cartList
  const cartList = ref([])
  // 获取最新购物车列表action
  const updateNewList = async () => {
    const res = await findNewCartListAPI()
    cartList.value = res.result
  }
  // 2. 定义action - addCart
  const addCart = async (goods) => {
    const { skuId, count } = goods
    if (isLogin.value) {
      // 登录之后的加入购车逻辑
      await insertCartAPI({ skuId, count })
      updateNewList()
    } else {
      // 添加购物车操作
      // 已添加过 - count + 1
      // 没有添加过 - 直接push
      // 思路：通过匹配传递过来的商品对象中的skuId能不能在cartList中找到，找到了就是添加过
      const item = cartList.value.find((item) => goods.skuId === item.skuId)
      if (item) {
        // 找到了
        item.count++
      } else {
        // 没找到
        cartList.value.push(goods)
      }
    }
  }

  // 删除购物车
  const delCart = async (skuId) => {
    if (isLogin.value) {
      // 调用接口实现接口购物车中的删除功能
      await delCartAPI([skuId])
      updateNewList()
    } else {
      // 思路：
      // 1. 找到要删除项的下标值 - splice
      // 2. 使用数组的过滤方法 - filter
      const idx = cartList.value.findIndex((item) => skuId === item.skuId)
      cartList.value.splice(idx, 1)
    }
  }

  // 清除购物车
  const clearCart = () => {
    cartList.value = []
  }

  // 单选功能
  const singleCheck = (skuId, selected) => {
    // 通过skuId找到要修改的那一项 然后把它的selected修改为传过来的selected
    const item = cartList.value.find((item) => item.skuId === skuId)
    item.selected = selected
  }

  // 全选功能
  const allCheck = (selected) => {
    // 把cartList中的每一项的selected都设置为当前的全选框状态
    cartList.value.forEach(item => item.selected = selected)
  }

  // 计算属性
  // 1. 总的数量 所有项的count之和
  const allCount = computed(() => cartList.value.reduce((a, c) => a + c.count, 0))
  // 2. 总价 所有项的count*price之和
  const allPrice = computed(() => cartList.value.reduce((a, c) => a + c.count * c.price, 0))

  // 3. 已选择数量
  const selectedCount = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count, 0))
  // 4. 已选择商品价钱合计
  const selectedPrice = computed(() => cartList.value.filter(item => item.selected).reduce((a, c) => a + c.count * c.price, 0))

  // 是否全选
  const isAll = computed(() => cartList.value.every((item) => item.selected))

  return {
    cartList,
    allCount,
    allPrice,
    isAll,
    selectedCount,
    selectedPrice,
    clearCart,
    addCart,
    delCart,
    singleCheck,
    allCheck,
    updateNewList
  }
}, {
  persist: true,
})

cartList/index.vue

<script setup>
import { useCartStore } from '@/stores/cartStore'
const cartStore = useCartStore()

// 单选回调
const singleCheck = (i, selected) => {
  console.log(i, selected)
  // store cartList 数组 无法知道要修改谁的选中状态？
  // 除了selected补充一个用来筛选的参数 - skuId
  cartStore.singleCheck(i.skuId, selected)
}
const allCheck = (selected) => {
  cartStore.allCheck(selected)
}
</script>

<template>
  <div class="xtx-cart-page">
    <div class="container m-top-20">
      <div class="cart">
        <table>
          <thead>
            <tr>
              <th width="120">
                <el-checkbox :model-value="cartStore.isAll" @change="allCheck" />
              </th>
              <th width="400">商品信息</th>
              <th width="220">单价</th>
              <th width="180">数量</th>
              <th width="180">小计</th>
              <th width="140">操作</th>
            </tr>
          </thead>
          <!-- 商品列表 -->
          <tbody>
            <tr v-for="i in cartStore.cartList" :key="i.id">
              <td>
                <!-- 单选框 -->
                <el-checkbox :model-value="i.selected" @change="(selected) => singleCheck(i, selected)" />
              </td>
              <td>
                <div class="goods">
                  <RouterLink to="/"><img :src="i.picture" alt="" /></RouterLink>
                  <div>
                    <p class="name ellipsis">
                      {{ i.name }}
                    </p>
                  </div>
                </div>
              </td>
              <td class="tc">
                <p>&yen;{{ i.price }}</p>
              </td>
              <td class="tc">
                <el-input-number v-model="i.count" />
              </td>
              <td class="tc">
                <p class="f16 red">&yen;{{ (i.price * i.count).toFixed(2) }}</p>
              </td>
              <td class="tc">
                <p>
                  <el-popconfirm title="确认删除吗?" confirm-button-text="确认" cancel-button-text="取消" @confirm="delCart(i)">
                    <template #reference>
                      <a href="javascript:;">删除</a>
                    </template>
                  </el-popconfirm>
                </p>
              </td>
            </tr>
            <tr v-if="cartStore.cartList.length === 0">
              <td colspan="6">
                <div class="cart-none">
                  <el-empty description="购物车列表为空">
                    <el-button type="primary">随便逛逛</el-button>
                  </el-empty>
                </div>
              </td>
            </tr>
          </tbody>

        </table>
      </div>
      <!-- 操作栏 -->
      <div class="action">
        <div class="batch">
          共 {{ cartStore.allCount }} 件商品，已选择 {{ cartStore.selectedCount }} 件，商品合计：
          <span class="red">¥ {{ cartStore.selectedPrice.toFixed(2) }} </span>
        </div>
        <div class="total">
          <el-button size="large" type="primary" @click="$router.push('/checkout')">下单结算</el-button>
        </div>
      </div>
    </div>
  </div>
</template>

<style scoped lang="scss">
.xtx-cart-page {
  margin-top: 20px;

  .cart {
    background: #fff;
    color: #666;

    table {
      border-spacing: 0;
      border-collapse: collapse;
      line-height: 24px;

      th,
      td {
        padding: 10px;
        border-bottom: 1px solid #f5f5f5;

        &:first-child {
          text-align: left;
          padding-left: 30px;
          color: #999;
        }
      }

      th {
        font-size: 16px;
        font-weight: normal;
        line-height: 50px;
      }
    }
  }

  .cart-none {
    text-align: center;
    padding: 120px 0;
    background: #fff;

    p {
      color: #999;
      padding: 20px 0;
    }
  }

  .tc {
    text-align: center;

    a {
      color: $xtxColor;
    }

    .xtx-numbox {
      margin: 0 auto;
      width: 120px;
    }
  }

  .red {
    color: $priceColor;
  }

  .green {
    color: $xtxColor;
  }

  .f16 {
    font-size: 16px;
  }

  .goods {
    display: flex;
    align-items: center;

    img {
      width: 100px;
      height: 100px;
    }

    >div {
      width: 280px;
      font-size: 16px;
      padding-left: 10px;

      .attr {
        font-size: 14px;
        color: #999;
      }
    }
  }

  .action {
    display: flex;
    background: #fff;
    margin-top: 20px;
    height: 80px;
    align-items: center;
    font-size: 16px;
    justify-content: space-between;
    padding: 0 30px;

    .xtx-checkbox {
      color: #999;
    }

    .batch {
      a {
        margin-left: 20px;
      }
    }

    .red {
      font-size: 18px;
      margin-right: 20px;
      font-weight: bold;
    }
  }

  .tit {
    color: #666;
    font-size: 16px;
    font-weight: normal;
    line-height: 50px;
  }

}
</style>