目的: Object 轉成 Array , Array 轉成Object
處理說明: 1>Object 轉成 Array - Object.entries(obj);
const obj = {
name: 'Luke Skywalker',
title: 'Jedi Knight',
age: 23
};
const Ary = Object.entries(obj);
2>Array 轉 Object - Object.fromEntries(Ary);
const Ary_filtered = Ary.filter( ([key, value]) => typeof value === 'string');
const obj_str = Object.fromEntries(Ary_filtered);
3>Sample:
const Obj_num = { 'BUF': 11, 'MIA': 9, 'NE': 6, 'NYJ': 1 };
const Ary_num= Object.entries(Obj_num );
Ary_num.filter( function(key,value){ return value>=9; } ); //正式函式寫法
Ary_num.filter( ([key,value]) => value>=9; ); //另一寫法
const Obj_num9=Object.fromEntries(Ary_num);
let rectangle = {width: 16, height: 9};
for (const key in rectangle)
let obj = {a: 1, b: 2, c: 3};
Object.entries()
直接取得所有 property 的 name 和 value,並以陣列回傳
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