vue购物车功能源码

<!DOCTYPE html>
<html lang="en">

<head>
<meta charset="UTF-8">
<title>Title</title>
<link href="http://cdn.static.runoob.com/libs/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
<style>
.cart {
50px;
height: 50px;
background: orangered;
text-align: center;
font-size: 20px;
position: fixed;
top: 400px;
right: 0;
}

.cart i {
color: #fff
}

.cart span {
display: block;
color: #fff;
}
</style>
</head>

<body>
<div id="app">
<div class="navbar navbar-inverse">
<div class="container-fluid">
<div class="navbar-header">
<a class="navbar-brand">珠峰购物车</a>
</div>
</div>
</div>

</div>
<script src="js/vue.js"></script>
<script src="https://unpkg.com/axios/dist/axios.min.js"></script>
<script>
let vm = new Vue({
el: '#app',
data: {
products: [],
current: '', //当前拖动的是哪个元素
carts: JSON.parse(localStorage.getItem('cartList')) || [],
},

filters: {
toInt(input) { // input = sum
return input.toFixed(2)
}
},
computed: {
count() {
return this.carts.reduce((prev, next) => {
return prev + parseInt(next.productCount);
}, 0)
},
checkall: {
get() { //如果products中有一个元素isSelected是false checkall则为false
//如果其中有一个返回为false 结果就是false
return this.carts.every(item => item.isSelected)
},
set(val) {
this.carts.forEach(item => item.isSelected = val)
}
},
sum() {
return this.carts.reduce((prev, next) => { //es5
if(next.isSelected) {
return prev + next.productCount * next.productPrice
} else {
return prev;
}
}, 0);
}
},
methods: {
remove(cart) { //filter过滤如果返回true 表示留下并且放到一个新的数组里
this.carts = this.carts.filter(item => item != cart); //es5
},
start(e, index) { //e.dataTransfer.setDragImg
//ref this.$refs.img
// 低版本浏览器不识别 chrome 需要60+
let product = { ...this.products[index],
productCount: 1,
isSelected: true
};
this.current = product; //保存当前拖动的那个元素
e.dataTransfer.setDragImage(this.$refs.img[index], 0, 0)
},
drop() {
//如果当前购物车中有则累加数量即可 this.current.id == this.carts其中一项如果相等
if(this.carts.some(item => item.id == this.current.id)) {
this.carts.forEach(item => {
if(item.id == this.current.id) {
item.productCount++;
}
});
} else {
this.carts.push(this.current);
}
}
},
created() { //created中的this 也是vm
//箭头函数中没有this指向
axios.get('./products.json').then(res => {
this.products = res.data;
})
},
});
</script>
</body>

</html>

不忘初心，方得始终，初心易得，始终难守。