ES6 filter的使用场景

1.有一个对象数组A，获取数组中指定类型的对象放到B数组中

//  ES6
var products = [{
  name: "苹果",
  type: "水果"
}, {
  name: "西蓝花",
  type: "蔬菜"
}, {
  name: "菠萝",
  type: "水果"
}];
var newProducts = products.filter(function(pro){
  return pro.type === "蔬菜"
})
console.log(newProducts);
           

var products = [{
  name: "苹果",
  type: "水果"
}, {
  name: "西蓝花",
  type: "蔬菜"
}, {
  name: "菠萝",
  type: "水果"
}];
var newProducts = [];
for(var i = 0; i < products.length; i++){
  if(products[i].type === "蔬菜"){
    newProducts.push(products[i]);
  }
}
console.log(newProducts); 
           

2.有一个对象数组A，过滤掉不满足以下条件的对象

条件：水果 数量大于0，价格小于10

var products = [{
    name: "苹果",
    type: "水果",
    price:15,
    quantity:2
  }, {
    name: "西蓝花",
    type: "蔬菜",
    price:5,
    quantity:2
  }, {
    name: "菠萝",
    type: "水果",
    price:5,
    quantity:2
  }];
  var newProducts = products.filter(function(pro){
    return pro.type === "水果" && pro.price < 10 && pro.quantity > 0;
  })
  console.log(newProducts);   // [{name: "菠萝", type: "水果", price: 5, quantity: 2}]
           

3.有两个数组A，B，根据A中的id值，过滤掉B数组中不符合的数据

var arr = {name: "苹果", type: "水果", price:15, quantity:2}
 var products = [{
   name: "苹果",
   type: "水果",
   price:15,
   quantity:2
 }, {
   name: "西蓝花",
   type: "蔬菜",
   price:5,
   quantity:2
 }, {
   name: "菠萝",
   type: "水果",
   price:5,
   quantity:2
 }];
 var newProducts = products.filter(function(pro){
   return pro.name === arr.name;
 })
 console.log(newProducts);  // [{name: "苹果", type: "水果", price: 15, quantity: 2}]