微信小程序实现购物车代码实例详解

onShow: function () {
  const cart = wx.getStorageSync("cart");
  let address = wx.getStorageSync("address") ;
  console.log(address);
  this.setData({
   address, cart
  })
  this.loadCarts();
  this.countAll();
 }

handleNumEdit(e) {
  const { operator, goodsid } = e.target.dataset;
  let { cart } = this.data;
  cart[goodsid].count += (+operator);
  if (cart[goodsid].count < 1) {
   cart[goodsid].count = 1;
   wx.showModal({
    title: '提示',
    content: '您确定要删除吗',
    showCancel: true,
    cancelText: '取消',
    cancelColor: '#000000',
    confirmText: '确定',
    confirmColor: '#3CC51F',
    success: (result) => {
     if (result.confirm) {
      delete cart[goodsid];
      this.loadCarts();
      this.countAll();
     } else {
     }
    }
   });
  } else if (cart[goodsid].count > cart[goodsid].goods_number) {
   cart[goodsid].count = cart[goodsid].goods_number;
   wx.showToast({
    title: '没有库存了',
    icon: 'none',
    duration: 1500,
    mask: true
   });
  }
  this.loadCarts();
  this.countAll();
 }

data: {
  cart: {},
  address: {},
  totalPrice: 0,
  categoryLength: 0,
  isAllChecked: true
 },

loadCarts() {
  let { cart } = this.data;
  let isAllChecked = true;
  for (const key in cart) {
   if (cart.hasOwnProperty(key)) {
    const element = cart[key];
    if (!element.isChecked) {
     isAllChecked = false;
     break;
    }
   }
  }
  this.setData({
   cart,
   isAllChecked
  });
 },

handleItemChecked(e) {
  let { goodsid } = e.target.dataset;
  let { cart } = this.data;
  let { isChecked } = cart[goodsid];
  cart[goodsid].isChecked = !isChecked;
  let checkedLength = 0;
  for (const key in cart) {
   if (cart.hasOwnProperty(key)) {
    if (cart[key].isChecked) {
     checkedLength++;
    }
   }
  }
  const isAllChecked = checkedLength == Object.keys(cart).length;
  this.countAll();
  this.setData({
   isAllChecked
  })
 },

handleItemAllChecked() {
  let { isAllChecked } = this.data;
  let { cart } = this.data;
  isAllChecked = !isAllChecked;
  for (const key in cart) {
   if (cart.hasOwnProperty(key)) {
    cart[key].isChecked = isAllChecked;
   }
  }
  this.setData({
   isAllChecked,
   cart
  })
  this.countAll();
 },