js二维数组转对象数组缺参

Question

var source = [
    [
        1,
        "黄蓉",
        1,
        "100"
    ],
    [
        2,
        "郭靖",
        1,
        "100"
    ]
];
var keys = ["no", "name", "cur_q", "rightrate"];

var result = source.map(vals => {
    return vals.reduce((obj, val) => {
        return Object.assign(obj, {[keys[vals.indexOf(val)]]: val})
    }, {})
})

console.log(result)

请问为什么第一行缺少了cur_q呀？
运行结果

[{"no":1,"name":"黄蓉","rightrate":"100"},{"no":2,"name":"郭靖","cur_q":1,"rightrate":"100"}]

Answer 1

var result = source.map(vals => {
    return vals.reduce((obj, val, index) => ({...obj, [keys[index]]: val}), {})
})

Answer 2

indexOf()方法返回在数组中可以找到一个给定元素的第一个索引