小程序实现购物车功能前后端代码（小程序实现购物车完整版）

<view wx:if="{{hasList}}">
  <view class="order_list">
    <view class="order" wx:for="{{list}}" wx:key="{{index}}">
      <view class="xuanze" wx:if="{{item.selected}}" catchtap="selectList" data-index="{{index}}">
        <image src="/images/serch/xuanze.png" />
      </view>
      <view class="xuanze" catchtap="selectList" data-index="{{index}}" wx:else>
        <image src="/images/serch/gouxuan.png" />
      </view>
      <!--列表商品图片-->
      <view class="order_img">
        <image src="{{item.image}}" />
      </view>
      <view class="order_text">
        <view class="text_top">
          <!--列表标题-->
          <view class="title">{{item.title}}</view>
          <view class="detel" catchtap="deletes" data-index="{{index}}">
            <image src="/images/serch/detel.png" />
          </view>
        </view>
        <!--规格-->
        <view class="size">规格：{{item.pro_name}}</view>
        <view class="text_bottom">
          <!--价格-->
          <view class="money">￥{{item.price}}</view>
          <!--商品数量加减-->
          <view class="number">
            <!--减按钮-->
            <view class="reduce" catchtap="btn_minus" data-obj="{{obj}}" data-index="{{index}}">
              <!--按钮图片-->
              <image src="/images/serch/jian-1.png" />
            </view>
            <!--数量-->
            <view class="numb">{{item.num}}</view>
            <!--加按钮-->
            <view class="add" catchtap="btn_add" data-index="{{index}}">
              <!--按钮图片-->
              <image src="/images/serch/add-1.png" />
            </view>
          </view>
        </view>
      </view>
    </view>
  </view>

  <!--固定底部-->
  <view class="buy">
    <view class="buy_top">
      <view class="top_left">
        <view class="left_img" catchtap="selectAll" wx:if="{{selectAllStatus}}">
          <image src="/images/serch/gouxuan.png" />
        </view>
        <view class="left_img" catchtap="selectAll" wx:else>
          <image src="/images/serch/gouxuan.png" />
        </view>
        <view class="left_name">全选</view>
      </view>
      <view class="top_left">
        <view class="left_img">
          <image src="/images/serch/fenxiang.png" />
        </view>
        <view class="left_name">分享</view>
      </view>
    </view>
    <view class="buy_bottom">
      <view class="buy_left">
        <view class="heji">合计：￥{{totalPrice}}</view>
      </view>
      <view class="buy_right">
        <!--提交订单-->
        <view class="liji " catchtap="btn_submit_order">立即购买</view>
        <view class="liji two active">预约试衣</view>
      </view>
    </view>
  </view>
</view>
<!--购物车没订单-->
<view wx:else>
  <view class="list_none">购物车是空的哦~</view>
</view>

page {
  background-color: rgba(238, 238, 238, 0.5);
}

.order {
  height: 238rpx;
  background-color: #fefeff;
  margin: 27rpx;
  border-radius: 4rpx;
  display: flex;
  align-items: center;
}

.xuanze {
  width: 40rpx;
  height: 40rpx;
  /* background-color: darkgoldenrod; */
  border-radius: 50%;
  margin: 0 11rpx;
}

.xuanze image {
  width: 100%;
  height: 100%;
  display: block;
  border-radius: 50%;
}

.order_img {
  width: 180rpx;
  height: 180rpx;
}

.order_img image {
  width: 100%;
  height: 100%;
  display: block;
}

.order_text {
  margin-left: 20rpx;
  width: 58%;
  height: 180rpx;
}

.text_top {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.title {
  width: 70%;
  font-size: 28rpx;
  color: #4b5248;
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 1;
  overflow: hidden;
}

.detel {
  width: 30rpx;
  height: 30rpx;
}

.detel image {
  width: 100%;
  height: 100%;
  display: block;
}

.size {
  font-size: 24rpx;
  color: #a8ada6;
}

.text_bottom {
  display: flex;
  margin-top: 50rpx;
  align-items: center;
  justify-content: space-between;
}

.money {
  font-size: 30rpx;
  color: #a5937f;
}

.number {
  display: flex;
  justify-content: space-around;
  align-items: center;
  width: 170rpx;
}

.reduce {
  width: 46rpx;
  height: 46rpx;
}

.reduce image {
  width: 100%;
  height: 100%;
  display: block;
}

.numb {
  font-size: 30rpx;
  color: #a5937f;
}

.add {
  width: 46rpx;
  height: 46rpx;
}

.add image {
  width: 100%;
  height: 100%;
  display: block;
}

/*购买按钮*/

.buy {
  height: 180rpx;
  width: 696rpx;
  position: fixed;
  left: 27rpx;
  bottom: 41rpx;
  background-color: #555555f3;
  border-radius: 4rpx;
}

.buy_top {
  border-bottom: 1px solid rgb(98, 98, 99);
  height: 75rpx;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.top_left {
  display: flex;
  align-items: center;
}

.left_img {
  width: 37rpx;
  height: 37rpx;
  margin: 11rpx;
}

.left_img image {
  width: 100%;
  height: 100%;
  display: block;
}

.left_name {
  font-size: 24rpx;
  color: #fefeff;
  margin-right: 29rpx;
}

.buy_bottom {
  display: flex;
  height: 104rpx;
  justify-content: space-between;
  align-items: center;
  padding: 0rpx 30rpx 0rpx 12rpx;
}

.buy_left {
  font-size: 26rpx;
  color: #fff;
}

.buy_right {
  display: flex;
  align-items: center;
}

.liji {
  width: 180rpx;
  height: 70rpx;
  border: 2rpx solid rgba(248, 248, 248, 1);
  box-sizing: border-box;
  border-radius: 4rpx;
  line-height: 70rpx;
  text-align: center;
  font-size: 26rpx;
  color: #FEFEFF;
}
.two{
  margin-left: 12rpx;
}
.active{
  background-color: #A5937F;
  border: none;
}

Page({

  /**
   * 页面的初始数据
   */
  data: {
    hasList: true, //默认展示列表数据
    //商品列表数据
    list: [{
        id: 1,
        title: '园艺大师抗皱精华露',
        image: '/images/serch/2.png',
        pro_name: "30ml",
        num: 1,
        price: 180,
        selected: true
      },
      {
        id: 2,
        title: '伊芙琳玫瑰护手霜',
        image: '/images/serch/1.png',
        pro_name: "25g",
        num: 1,
        price: 62,
        selected: true
      },
      {
        id: 2,
        title: '燕麦山羊乳舒缓护手霜',
        image: '/images/serch/2.png',
        pro_name: "75ml",
        num: 1,
        price: 175,
        selected: true
      }
    ],
    //金额
    totalPrice: 0, //总价，初始为0
    //全选状态
    selectAllStatus: true, // 全选状态，默认全选
  },

  /**
   * 生命周期函数--监听页面加载
   */
  onLoad: function(options) {

  },

  /**
   * 生命周期函数--监听页面显示
   */
  onShow: function() {
    wx.showToast({
      title: '加载中',
      icon: "loading",
      duration: 1000
    })
    // 价格方法
    this.count_price();

  },

  /** 当前商品选中事件 */
  selectList(e) {
    var that = this;
    //获取选中的 radio索引
    var index = e.currentTarget.dataset.index;
    //获取到商品列表数据
    var list = that.data.list;
    //默认全选
    that.data.selectAllStatus = true;
    //循环数组数据，判断--选中/未选中[selected]
    list[index].selected = !list[index].selected;
    //如果数组数据全部为selected[true],全选
    for (var i = list.length - 1; i >= 0; i--) {
      if (!list[i].selected) {
        that.data.selectAllStatus = false;
        break;
      }
    }
    // 重新渲染数据
    that.setData({
      list: list,
      selectAllStatus: that.data.selectAllStatus
    })
    // 调用计算金额方法
    that.count_price();
  },

  // 删除
  deletes(e) {
    var that = this;
    // 获取索引
    const index = e.currentTarget.dataset.index;
    // 获取商品列表数据
    let list = this.data.list;
    wx.showModal({
      title: '提示',
      content: '确认删除吗',
      success: function(res) {
        if (res.confirm) {
          // 删除索引从1
          list.splice(index, 1);
          // 页面渲染数据
          that.setData({
            list: list
          });
          // 如果数据为空
          if (!list.length) {
            that.setData({
              hasList: false
            });
          } else {
            // 调用金额渲染数据
            that.count_price();
          }
        } else {
          console.log(res);
        }
      },
      fail: function(res) {
        console.log(res);
      }
    })
  },

  /** 购物车全选事件 */
  selectAll(e) {
    // 全选ICON默认选中
    let selectAllStatus = this.data.selectAllStatus;
    // true  -----   false
    selectAllStatus = !selectAllStatus;
    // 获取商品数据
    let list = this.data.list;
    // 循环遍历判断列表中的数据是否选中
    for (let i = 0; i < list.length; i++) {
      list[i].selected = selectAllStatus;
    }
    // 页面重新渲染
    this.setData({
      selectAllStatus: selectAllStatus,
      list: list
    });
    // 计算金额方法
    this.count_price();
  },

  /** 绑定加数量事件 */
  btn_add(e) {
    // 获取点击的索引
    const index = e.currentTarget.dataset.index;
    // 获取商品数据
    let list = this.data.list;
    // 获取商品数量
    let num = list[index].num;
    // 点击递增
    num = num + 1;
    list[index].num = num;
    // 重新渲染 ---显示新的数量
    this.setData({
      list: list
    });
    // 计算金额方法
    this.count_price();
  },

  /**
   * 绑定减数量事件
   */
  btn_minus(e) {
    //   // 获取点击的索引
    const index = e.currentTarget.dataset.index;
    // const obj = e.currentTarget.dataset.obj;
    // console.log(obj);
    // 获取商品数据
    let list = this.data.list;
    // 获取商品数量
    let num = list[index].num;
    // 判断num小于等于1  return; 点击无效
    if (num <= 1) {
      return false;
    }
    // else  num大于1  点击减按钮  数量--
    num = num - 1;
    list[index].num = num;
    // 渲染页面
    this.setData({
      list: list
    });
    // 调用计算金额方法
    this.count_price();
  },

  // 提交订单
  btn_submit_order() {
    var that = this;
    console.log(that.data.totalPrice);

    // 调起支付
    // wx.requestPayment(
    //   {
    //     'timeStamp': '',
    //     'nonceStr': '',
    //     'package': '',
    //     'signType': 'MD5',
    //     'paySign': '',
    //     'success': function (res) { },
    //     'fail': function (res) { },
    //     'complete': function (res) { }
    //   })
    wx.showModal({
      title: '提示',
      content: '合计金额-' + that.data.totalPrice + "暂未开发",
    })
  },

  /**
   * 计算总价
   */
  count_price() {
    // 获取商品列表数据
    let list = this.data.list;
    // 声明一个变量接收数组列表price
    let total = 0;
    // 循环列表得到每个数据
    for (let i = 0; i < list.length; i++) {
      // 判断选中计算价格
      if (list[i].selected) {
        // 所有价格加起来 count_money
        total += list[i].num * list[i].price;
      }
    }
    // 最后赋值到data中渲染到页面
    this.setData({
      list: list,
      totalPrice: total.toFixed(2)
    });
  },

})