如果你使用ES6，你可以使用Object。赋值运算符和展开运算符

{ ...['a', 'b', 'c'] }

如果你有嵌套数组

var arr=[[1,2,3,4]]
Object.assign(...arr.map(d => ({[d[0]]: d[1]})))

为什么没人尝试?在ES6

let arr = ['a','b','c']
let {...obj} = arr
console.log(obj) //  {0: 'a', 1: 'b', 2: 'c'}

let {...obj2} = ['a','b','c']
console.log(obj2) //  {0: 'a', 1: 'b', 2: 'c'}

很简单的方法吗?

我曾多次遇到过这个问题，并决定编写一个尽可能通用的函数。看一看，可以随意修改吗

function typeOf(obj) {
    if ( typeof(obj) == 'object' ) {
        if (obj.length)
            return 'array';
        else
            return 'object';
    } else
    return typeof(obj);
}

function objToArray(obj, ignoreKeys) {
    var arr = [];
    if (typeOf(obj) == 'object') {
        for (var key in obj) {
            if (typeOf(obj[key]) == 'object') {
                if (ignoreKeys)
                    arr.push(objToArray(obj[key],ignoreKeys));
                else
                    arr.push([key,objToArray(obj[key])]);
            }
            else
                arr.push(obj[key]);
        }
    }else if (typeOf(obj) == 'array') {
        for (var key=0;key<obj.length;key++) {
            if (typeOf(obj[key]) == 'object')
                arr.push(objToArray(obj[key]));
            else
                arr.push(obj[key]);
        }
    }
    return arr;
}

如果你正在使用jquery:

$.extend({}, ['a', 'b', 'c']);

使用javascript简化很简单:

["a", "b", "c", "d"].reduce(function(previousValue, currentValue, index) { 
   previousValue[index] = currentValue; 
   return previousValue;
}, 
{}
);

你可以看看Array.prototype.reduce()， https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/Reduce

import books from "./books.json";

export const getAllBooks = () => {
  return {
    data: books,
    // a=accoumulator, b=book (data itelf), i=index
    bookMap: books.reduce((a, book, i) => {
      // since we passed {} as initial data, initially a={}
      // {bookID1:book1, bookID2:i}
      a[book.id] = book;
      // you can add new property index
      a[book.id].index=i
      return a;
      // we are passing initial data structure
    }, {}),
  };
};