对象数组上的下划线循环修改某些对象并删除某些对象

Question

假设我有对象数组，

[{"month":"03-2016","isLate":"N","transactionCount":4,"transactionAmount":8746455},{"month":"05-2016","isLate":"N","transactionCount":5,"transactionAmount":-40004952945.61},{"month":"06-2016","isLate":"N","transactionCount":1,"transactionAmount":100000},{"month":"04-2016","isLate":"N","transactionCount":6,"transactionAmount":-117189.89},{"month":"02-2016","isLate":"N","transactionCount":4,"transactionAmount":-5331000},{"month":"04-2016","isLate":null,"transactionCount":2,"transactionAmount":-4888.89},{"month":"03-2016","isLate":null,"transactionCount":3,"transactionAmount":5000}]

下划线或 javascript 中是否有一个函数，我可以在其中循环项目，根据某些条件，删除某些对象，否则修改对象（向对象添加更多信息）和 return数据。

Answer 1

是的，有 filter()

var resArray = myArray.filter(x => x.transactionCount != 1);

在这个例子中，我删除了属性个交易计数 === 1

的元素

Answer 2

你可以用普通的 JavaScript:

删除某些对象：使用 filter()
修改对象（向对象添加更多信息）：使用map()

例如：

var input = [
  {
    "month": "03-2016",
    "isLate": "N",
    "transactionCount": 4,
    "transactionAmount": 8746455
  },
  {
    "month": "05-2016",
    "isLate": "N",
    "transactionCount": 5,
    "transactionAmount": -40004952945.61
  },
  {
    "month": "06-2016",
    "isLate": "N",
    "transactionCount": 1,
    "transactionAmount": 100000
  },
  {
    "month": "04-2016",
    "isLate": "N",
    "transactionCount": 6,
    "transactionAmount": -117189.89
  },
  {
    "month": "02-2016",
    "isLate": "N",
    "transactionCount": 4,
    "transactionAmount": -5331000
  },
  {
    "month": "04-2016",
    "isLate": null,
    "transactionCount": 2,
    "transactionAmount": -4888.89
  },
  {
    "month": "03-2016",
    "isLate": null,
    "transactionCount": 3,
    "transactionAmount": 5000
  }
];

// Helper array to translate month number to month name 
var monthNames = ["January", "February", "March", "April", "May", "June",
  "July", "August", "September", "October", "November", "December"
];

input = input
    // only get the entries which don't have isLate=N:
    .filter( o => o.isLate !== 'N' )
    // add a property "mm":
    .map( o => Object.assign(o, { mm: monthNames[+o.month.substr(0,2)-1] }) );

// Output result
console.log(input);

对于不支持 ES6 的 JavaScript 环境，将 input = 语句替换为：

input = input
    // only get the entries which don't have isLate=N:
    .filter( function (o) {
        return o.isLate !== 'N'; 
    })
    // add a property "mm":
    .map( function (o) {
        o.mm = monthNames[+o.month.substr(0,2)-1];
        return o;
    });

对象数组上的下划线循环修改某些对象并删除某些对象

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