如何将键值元组数组转换为对象

Question

我有一个数组:

[ [ 'cardType', 'iDEBIT' ],
  [ 'txnAmount', '17.64' ],
  [ 'txnId', '20181' ],
  [ 'txnType', 'Purchase' ],
  [ 'txnDate', '2015/08/13 21:50:04' ],
  [ 'respCode', '0' ],
  [ 'isoCode', '0' ],
  [ 'authCode', '' ],
  [ 'acquirerInvoice', '0' ],
  [ 'message', '' ],
  [ 'isComplete', 'true' ],
  [ 'isTimeout', 'false' ] ]

但我不能通过数组的密钥访问数据,例如arr['txnId']不返回20181.如何将上面的元组数组转换为对象,以便我可以通过键轻松访问数据.

Answer 1

如果您正在使用ES6,则可以使用Object.assign和spread运算符来使用map而不是@ royhowie的reduce,这可能会也可能不会更直观:

Object.assign(...arr.map(([key, val]) => ({[key]: val})))

例如:

var arr = [ [ 'cardType', 'iDEBIT' ],
  [ 'txnAmount', '17.64' ],
  [ 'txnId', '20181' ],
  [ 'txnType', 'Purchase' ],
  [ 'txnDate', '2015/08/13 21:50:04' ],
  [ 'respCode', '0' ],
  [ 'isoCode', '0' ],
  [ 'authCode', '' ],
  [ 'acquirerInvoice', '0' ],
  [ 'message', '' ],
  [ 'isComplete', 'true' ],
  [ 'isTimeout', 'false' ] ]

var obj = Object.assign(...arr.map(([key, val]) => ({[key]: val})))

console.log(obj)

Answer 2

更惯用的方法是使用Array.prototype.reduce:

var arr = [
  [ 'cardType', 'iDEBIT' ],
  [ 'txnAmount', '17.64' ],
  [ 'txnId', '20181' ],
  [ 'txnType', 'Purchase' ],
  [ 'txnDate', '2015/08/13 21:50:04' ],
  [ 'respCode', '0' ],
  [ 'isoCode', '0' ],
  [ 'authCode', '' ],
  [ 'acquirerInvoice', '0' ],
  [ 'message', '' ],
  [ 'isComplete', 'true' ],
  [ 'isTimeout', 'false' ]
];

var obj = arr.reduce(function (o, currentArray) {
  var key = currentArray[0], value = currentArray[1]
  o[key] = value
  return o
}, {})

console.log(obj)
document.write(JSON.stringify(obj).split(',').join(',<br>'))

使用ES6(rest parameters)语法完成后,这在视觉上更具吸引力:

let obj = arr.reduce((o, [ key, value ]) => {
    o[key] = value
    return o
}, {})

Answer 3

这样做:

array =    [ [ 'cardType', 'iDEBIT' ],
      [ 'txnAmount', '17.64' ],
      [ 'txnId', '20181' ],
      [ 'txnType', 'Purchase' ],
      [ 'txnDate', '2015/08/13 21:50:04' ],
      [ 'respCode', '0' ],
      [ 'isoCode', '0' ],
      [ 'authCode', '' ],
      [ 'acquirerInvoice', '0' ],
      [ 'message', '' ],
      [ 'isComplete', 'true' ],
      [ 'isTimeout', 'false' ] ];
    
var obj = {};
array.forEach(function(data){
    obj[data[0]] = data[1]
});
console.log(obj);

Answer 4

使用地图.

new Map(array);

这是有效的,因为变量的类型array是Array<[key,value]>.该Map构造可以与阵列的阵列,其中所述内阵列的第一个元素是密钥和第二是值被初始化.

const array = [
  ['cardType', 'iDEBIT'],
  ['txnAmount', '17.64'],
  ['txnId', '20181'],
  ['txnType', 'Purchase'],
  ['txnDate', '2015/08/13 21:50:04'],
  ['respCode', '0'],
  ['isoCode', '0'],
  ['authCode', ''],
  ['acquirerInvoice', '0'],
  ['message', ''],
  ['isComplete', 'true'],
  ['isTimeout', 'false']
];

const obj = new Map(array);

console.log(obj.get('txnDate'));

Answer 5

arr.reduce((o, [key, value]) => ({...o, [key]: value}), {})

Answer 6

使用Object.fromEntries，您可以从 转换Array为Object：

var entries = [
  ['cardType', 'iDEBIT'],
  ['txnAmount', '17.64'],
  ['txnId', '20181'],
  ['txnType', 'Purchase'],
  ['txnDate', '2015/08/13 21:50:04'],
  ['respCode', '0'],
  ['isoCode', '0'],
  ['authCode', ''],
  ['acquirerInvoice', '0'],
  ['message', ''],
  ['isComplete', 'true'],
  ['isTimeout', 'false']
];
var obj = Object.fromEntries(entries);
console.log(obj);