将JSON对象映射到Javascript类

Question

I want to know the "good practice" to map a JSON object to a Javascript instance Class.

My example is that I have a database of Cards in a JSON file. Each Card has several attributes. I have a Class Card that has the same attributes plus several methods. How to map the Cards in the JSON file into instances of the Class Card, without copying each attribute one by one if able ?

I have a JSON objects from a JSON file. Here is an example but I have 700 objects like these :

{"cycleId":1,"setId":1,"cardId":27,"nameEn":"Ninja","nameFr":"Ninja","side":"RUNNER","cardTypes":["PROGRAM","ICE_BREAKER","KILLER"],"nbCopies":3,"rarity":"UNCO"},
{"cycleId":1,"setId":1,"cardId":29,"nameEn":"Bank Job","nameFr":"Casse","side":"RUNNER","cardTypes":["RESOURCE"],"nbCopies":3,"rarity":"COMMON"}

I retrieve these JSON file by an AJAX request :

$.ajax({
        url: databaseUrl,
        beforeSend: function(xhr){
          if (xhr.overrideMimeType)
          {
            xhr.overrideMimeType("application/json");
          }
        },
        async:true,
        global: false,
        dataType: 'json',
        data:fieldString,
        success: function(data, status, request) {
          // >> Here I want to MAP the JSON data into Class instances <<
        }
      });

The Class Card where to map the JSON data :

function Card(cycleId, setId...) {
  // One example of a method
  this.calculateScore = function(cardTypes, rarity) {
    var score = 0;
    // Calculates the score of the Card according to the specified parameters and the attributes of the Card
    ...
    return score;
  }
}

Thank you for your help.

Answer 1

Not sure if this is what you're asking but you could do this

function Card(obj) {
  // The attributes of "obj" to map to this class
  var keys = ["cardTypes", "rarity", ...];
  for (var key in obj) {
      if (obj.hasOwnProperty(key) && keys.indexOf(key) !== -1) {
          this[key] = obj[key];
      }
  }
  // One example of a method
  this.calculateScore = function(cardTypes, rarity) {
    var score = 0;
    // Calculates the score of the Card according to the specified parameters and the attributes of the Card
    ...
    return score;
  }
}

Answer 2

Take a look at this: how I experimented with it 2 years ago

I am not using this in practice much, instead what is popular solution these days is to have code generation as part of the development process that produces the code you would write by hand otherwise that does exactly that: copying values from plain JS objects to Class properties plus it might make some checks as well (for example if the type is correct and possibly convert types, it also provides the reverse mapping (toJSON which is automatically picked up by JSON.stringify) and can also map names (JS object name to Class name). For an example take a look here - battle tested, contains all of the above:

• name mapping
• type checking
• type conversion (inc Date)
• support for nested objects and arrays