Lodash中的對象逆變器而不會丟失密鑰

Question

嘗試使用_.invert對象，將舊鍵收集到一個數組中，而不是丟失它們。

這是我設法做到的方法：

 let tokens = { y: 'years', Y: 'years', M: 'months', mo: 'months', Mo: 'months', w: 'weeks', W: 'weeks', d: 'days', D: 'days', h: 'hours', H: 'hours', m: 'minutes', mi: 'minutes', Mi: 'minutes', s: 'seconds', S: 'ms' }, print = JSON.stringify(inverter(tokens), null, 2); document.querySelector('#test').innerHTML = print; function inverter(obj) { let out = {}; _.forOwn(obj, (o, k) => { out[o] = _.concat(out[o] || [], [k]); }); return out; } 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js"></script> <pre id="test"></pre> 

大多數時候，我感覺到我對lib的使用就像一把游泳錘一樣優雅，所以我的問題是：有沒有一種比我當前的converter inverter()函數更簡單，更優雅的“ lodashy”方式？

Answer 1

使用_.invertBy() 。 根據文檔：

每個反轉鍵的相應反轉值是負責生成反轉值的鍵的數組。

 const tokens = {"y":"years","Y":"years","M":"months","mo":"months","Mo":"months","w":"weeks","W":"weeks","d":"days","D":"days","h":"hours","H":"hours","m":"minutes","mi":"minutes","Mi":"minutes","s":"seconds","S":"ms"}; const result = _.invertBy(tokens); console.log(result); 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.5/lodash.min.js"></script> <pre id="test"></pre> 

Answer 2

使用Lodash 4.1.0或更高版本，您應該能夠做到：

_.invertBy({
  y: 'years',
  Y: 'years',
  M: 'months',
  mo: 'months',
  Mo: 'months',
  w: 'weeks',
  W: 'weeks',
  d: 'days',
  D: 'days',
  h: 'hours',
  H: 'hours',
  m: 'minutes',
  mi: 'minutes',
  Mi: 'minutes',
  s: 'seconds',
  S: 'ms'
});