javascript - IE不支持传播运算符（...）如何解决此问题(IE does not support the spread operator (…) how to fix this issue)

Question

    var cars = [{
    make: "audi",
    model: "r8",
    year: "2012"
    },
    {
    make: "audi",
    model: "rs5",
    year: "2013"
    },
    {
    make: "ford",
    model: "mustang",
    year: "2012"
    },
    {
    make: "ford",
    model: "fusion",
    year: "2015"
    },
    {
    make: "kia",
    model: "optima",
    year: "2012"
    }];    
var group = cars.reduce((r, a) => {
        console.log("a", a);
        console.log('r', r);
r[a.make] = [...r[a.make] || [], a];
return r;
}, {});

I want to make it a group of an array but This code doesn't work in IE so can anyone help me out to make it work in IE browser.(我想使其成为一组数组，但是此代码在IE中不起作用，因此任何人都可以帮助我使其在IE浏览器中起作用。)

  ask by Dinesh ghimire translate from so

Answer 1

The modified answer address two issues with IE.(修改后的答案解决了IE的两个问题。)

IE does not support arrow functions(IE不支持箭头功能) IE does not support the spread operator(IE不支持点差运算符) So the logic is pretty simple.(因此逻辑很简单。) If the make key is not in the result, put a new empty array in the result for the key.(如果make键不在结果中，请在该键的结果中放入一个新的空数组。) And then just push the value to it.(然后将价值推向它。) var cars = [{ make: "audi", model: "r8", year: "2012" }, { make: "audi", model: "rs5", year: "2013" }, { make: "ford", model: "mustang", year: "2012" }, { make: "ford", model: "fusion", year: "2015" }, { make: "kia", model: "optima", year: "2012" } ]; var group = cars.reduce(function(r, a) { r[a.make] = (r[a.make] || []); r[a.make].push(a); return r; }, {}); console.log(group);