javascript - 遍历对象时遇到问题

Question

我有一个看起来像这样的对象:

salesDetails:{ "1":{
  "date":"06/22/2014",
  "amount":"45",
  "currency":"CAD",
  "productID":"23",
  "status":1},
"2":{
  "date":"06/22/2014",
  "amount":"120",
  "currency":"USD",
  "productID":"23",
  "status":1},
"3":{
  "date":"06/23/2014",
  "amount":"100",
  "currency":"USD",
  "productID":"21",
  "status":2},
"4":{
  "date":"06/23/2014",
  "amount":"250",
  "currency":"CAD",
  "productID":"25",
  "status":1},
"5":{
  "date":"06/23/2014",
  "amount":"180",
  "currency":"USD",
  "productID":"24",
  "status":1}
}

我想做的是获取所有状态为“1”的货币的所有金额，并将其放入应如下所示的对象中:

perCurrency: {
 "CAD":{
  "0":"45", 
  "1":"250"},

 "USD":{
  "0":"120",
  "1":"180"}
}

我能够将所有货币放入一个对象中，但我在金额方面遇到了麻烦，对象中的最后一个金额与前一个金额重叠。我不断收到 {"CAD":{"1":"250"},"USD":{"1":"180"}} 到目前为止，这是我的代码。

function countPerCurrency(){
  var currencyArray = new Array();
  var perCurrency = {}; 

  var totalSales = Object.size(salesDetails);

  for(var i=1; i <= totalSales; i++){
    var currency = salesDetails[i]["currency"];
    var amount = salesDetails[i]["amount"];
    var status = salesDetails[i]["status"];

    var totalCurrency = Object.size(currencyAmount[currency]);
    var currencyCtr = {};

    if(status == 1){
      if(!inArray(currency, currencyArray)){
        currencyArray.push(currency);
        currencyCtr[totalCurrency] = amount;
        perCurrency[currency] = currencyCtr;
      } else {
        var currencyAdd = {};
        currencyAdd[totalCurrency] = amount;
        perCurrency[currency] = currencyAdd;
      }
    }
  }         
}

我知道这可能看起来很容易，但我在这里迷路了..TIA! :)

Answer 1

之前接受的答案使用一个值数组，而您要求一个对象。这是一个对象版本:

var perCurrency = {};
var currencyCount = {};

Object.keys(salesDetails).forEach(function(key) {
  var obj = salesDetails[key];
  var currency;

  if (obj.status == 1) {
    currency = obj.currency;

    // If this is first for this currency, add it to objects
    if (!currencyCount[currency]) {
      currencyCount[currency] = 0;
      perCurrency[currency] = {};
    }

    // Add currency values
    perCurrency[currency][currencyCount[currency]++] = obj.amount;
  }
}); 

顺便说一句，这与 jQuery 无关。

请注意，Object.keys 是 ES5，因此可能需要针对旧版浏览器的 polyfill，请参阅 MDN:Object.keys代码。