从数组将对象数组转换为对象的对象特性

可以将数组作为参数展开( spread syntax ... )为了 Object.assign ,返回单个对象。

const
    array = [{ book: 5, car: 6, pc: 7 }, { headphone: 9, keyboard: 10 }],
    object = Object.assign({}, ...array);
    
console.log(object);

.reduce() 和 Object.assign() 方法:

const array = [
  {book:5, car: 6, pc: 7},
  {headphone: 9, keyboard: 10},
];

const result = array.reduce((r, c) => Object.assign(r, c), {});

console.log(result);

for(let i = 0; i < array.length; i++){
    for (let key in array[i]) {
        if (array[i].hasOwnProperty(key)) {
            obj[key] = array[i][key];
        }
    }
}

怎么样

let obj = {}

for(let object of array) {
  Object.assign(obj, object)
}

console.log(obj)