编写一套小程序商城的代码

A：以下是一套简单的小程序商城代码：

HTML部分：

<view class="container">
  <view class="goods-list">
    <view class="goods" wx:for="{{goodsList}}" wx:key="{{item.id}}" bindtap="onGoodsTap">
      <image class="img" src="{{item.imgUrl}}"></image>
      <view class="name">{{item.name}}</view>
      <view class="price">{{item.price}}</view>
    </view>
  </view>
  <view class="footer">
    <view class="shopping-cart" bindtap="onCartTap">
      <image class="icon" src="/images/cart.png"></image>
      <view class="count">{{cartCount}}</view>
    </view>
    <view class="buy-btn" bindtap="onBuyTap">
      <view class="text">立即购买</view>
    </view>
  </view>
</view>

CSS部分：

.container {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  height: 100%;
}
.goods-list {
  flex: 1;
  overflow-y: scroll;
  width: 100%;
  padding: 20rpx;
}
.goods {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 100%;
  height: 380rpx;
  border-radius: 10rpx;
  box-shadow: 0 0 10rpx 0 rgba(23, 23, 23, 0.1);
  margin-bottom: 20rpx;
}
.img {
  height: 280rpx;
  width: 280rpx;
  border-radius: 10rpx;
  margin-bottom: 20rpx;
}
.name {
  font-size: 30rpx;
  color: #333;
  margin-bottom: 10rpx;
}
.price {
  font-size: 24rpx;
  color: #f00;
}
.footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  height: 100rpx;
  background-color: #fff;
  box-shadow: 0 -2rpx 6rpx 0 rgba(23, 23, 23, 0.1);
  position: fixed;
  bottom: 0;
  left: 0;
}
.shopping-cart {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  width: 140rpx;
  height: 100%;
  margin-right: 20rpx;
}
.icon {
  height: 40rpx;
  width: 40rpx;
}
.count {
  display: flex;
  justify-content: center;
  align-items: center;
  position: absolute;
  top: 0;
  right: 0;
  height: 30rpx;
  width: 30rpx;
  background-color: #f00;
  border-radius: 15rpx;
  color: #fff;
  font-size: 18rpx;
}
.buy-btn {
  display: flex;
  justify-content: center;
  align-items: center;
  width: 280rpx;
  height: 80rpx;
  background-color: #f00;
  border-radius: 40rpx;
}
.text {
  color: #fff;
  font-size: 28rpx;
}

JavaScript部分：

// 初始化数据
const goodsList = [{
  id: 1,
  imgUrl: '/images/goods-1.jpg',
  name: '商品1',
  price: 99.00
}, {
  id: 2,
  imgUrl: '/images/goods-2.jpg',
  name: '商品2',
  price: 199.00
}, {
  id: 3,
  imgUrl: '/images/goods-3.jpg',
  name: '商品3',
  price: 299.00
}, {
  id: 4,
  imgUrl: '/images/goods-4.jpg',
  name: '商品4',
  price: 399.00
}, {
  id: 5,
  imgUrl: '/images/goods-5.jpg',
  name: '商品5',
  price: 499.00
}]
const cart = []
const cartCount = 0

Page({
  data: {
    goodsList: goodsList,
    cartCount: cartCount
  },
  onGoodsTap: function(e) {
    const goodsId = e.currentTarget.dataset.id
    wx.navigateTo({
      url: '/pages/goods-detail/goods-detail?id=' + goodsId
    })
  },
  onCartTap: function() {
    wx.navigateTo({
      url: '/pages/shopping-cart/shopping-cart'
    })
  },
  onBuyTap: function() {
    if (cart.length === 0) {
      wx.showToast({
        title: '购物车没有商品',
        icon: 'none'
      })
    } else {
      wx.navigateTo({
        url: '/pages/checkout/checkout'
      })
    }
  }
})

以上代码包含了一个商品列表页面，可以点击商品进入商品详情页，也可以点击底部购物车按钮查看购物车列表，还可以点击底部立即购买按钮，跳转到结算页面。购物车和结算页面的代码还需根据需求开发。