>[success] # 30s Object -- 增(一) ~~~ 1.本章節代碼通過整理30s 項目中數組篇章知識點，對涉及對象增邏輯的片段整理 ~~~ >[info] ## 根據給定的鍵值對創建一個對象 ~~~ 1.現在給定了一個鍵值對數組，想轉換將 [['a', 1], ['b', 2]] =》{a: 1, b: 2} ~~~ [object-from-pairs](https://www.30secondsofcode.org/js/s/object-from-pairs) >[danger] ##### 30s ~~~ const log = console.log const objectFromPairs = arr=> arr.reduce((acc,[key,val])=>(acc[key]= val,acc),{}) log(objectFromPairs([['a', 1], ['b', 2]])) ~~~ >[danger] ##### 30s 從對象到數組 [object-to-entries](https://www.30secondsofcode.org/js/s/object-to-entries) ~~~ 1.將對象反解析成數組key,val 形式 2.先通過Object.keys 和map 組合形成想要的格式展示 或者直接使用'Object.entries' ~~~ ~~~ const log = console.log const objectToEntries = obj=> Object.keys(obj).map(key=>[key,obj[key]]) log(objectToEntries({ a: 1, b: 2 })) // [ [ 'a', 1 ], [ 'b', 2 ] ] // Object.entries const objectToPairs = obj => Object.entries(obj); objectToPairs({ a: 1, b: 2 }); // [ ['a', 1], ['b', 2] ] ~~~