[javascript] Parse JSON String into a Particular Object Prototype in JavaScript

I've combined the solutions that I was able to find and compiled it into a generic one that can automatically parse a custom object and all it's fields recursively so you can use prototype methods after deserialization.

One assumption is that you defined a special filed that indicates it's type in every object you want to apply it's type automatically (this.__type in the example).

function Msg(data) {
    //... your init code
    this.data = data //can be another object or an array of objects of custom types. 
                     //If those objects defines `this.__type', their types will be assigned automatically as well
    this.__type = "Msg"; // <- store the object's type to assign it automatically
}

Msg.prototype = {
    createErrorMsg: function(errorMsg){
        return new Msg(0, null, errorMsg)
    },
    isSuccess: function(){
        return this.errorMsg == null;
    }
}

usage:

var responseMsg = //json string of Msg object received;
responseMsg = assignType(responseMsg);

if(responseMsg.isSuccess()){ // isSuccess() is now available
      //furhter logic
      //...
}

Type assignment function (it work recursively to assign types to any nested objects; it also iterates through arrays to find any suitable objects):

function assignType(object){
    if(object && typeof(object) === 'object' && window[object.__type]) {
        object = assignTypeRecursion(object.__type, object);
    }
    return object;
}

function assignTypeRecursion(type, object){
    for (var key in object) {
        if (object.hasOwnProperty(key)) {
            var obj = object[key];
            if(Array.isArray(obj)){
                 for(var i = 0; i < obj.length; ++i){
                     var arrItem = obj[i];
                     if(arrItem && typeof(arrItem) === 'object' && window[arrItem.__type]) {
                         obj[i] = assignTypeRecursion(arrItem.__type, arrItem);
                     }
                 }
            } else  if(obj && typeof(obj) === 'object' && window[obj.__type]) {
                object[key] = assignTypeRecursion(obj.__type, obj);
            }
        }
    }
    return Object.assign(new window[type](), object);
}

Examples related to javascript

need to add a class to an element How to make a variable accessible outside a function? Hide Signs that Meteor.js was Used How to create a showdown.js markdown extension Please help me convert this script to a simple image slider Highlight Anchor Links when user manually scrolls? Summing radio input values How to execute an action before close metro app WinJS javascript, for loop defines a dynamic variable name Getting all files in directory with ajax

Examples related to json

Use NSInteger as array index Uncaught SyntaxError: Unexpected end of JSON input at JSON.parse (<anonymous>) HTTP POST with Json on Body - Flutter/Dart Importing json file in TypeScript json.decoder.JSONDecodeError: Extra data: line 2 column 1 (char 190) Angular 5 Service to read local .json file How to import JSON File into a TypeScript file? Use Async/Await with Axios in React.js Uncaught SyntaxError: Unexpected token u in JSON at position 0 how to remove json object key and value.?

Examples related to parsing

Got a NumberFormatException while trying to parse a text file for objects Uncaught SyntaxError: Unexpected end of JSON input at JSON.parse (<anonymous>) Python/Json:Expecting property name enclosed in double quotes Correctly Parsing JSON in Swift 3 How to get response as String using retrofit without using GSON or any other library in android UIButton action in table view cell "Expected BEGIN_OBJECT but was STRING at line 1 column 1" How to convert an XML file to nice pandas dataframe? How to extract multiple JSON objects from one file? How to sum digits of an integer in java?

Examples related to object

How to update an "array of objects" with Firestore? how to remove json object key and value.? Cast object to interface in TypeScript Angular 4 default radio button checked by default How to use Object.values with typescript? How to map an array of objects in React How to group an array of objects by key push object into array Add property to an array of objects access key and value of object using *ngFor

Examples related to prototype

What are the nuances of scope prototypal / prototypical inheritance in AngularJS? Extending an Object in Javascript __proto__ VS. prototype in JavaScript Parse JSON String into a Particular Object Prototype in JavaScript Understanding the difference between Object.create() and new SomeFunction() 'this' is undefined in JavaScript class methods JavaScript: What are .extend and .prototype used for? Calling method using JavaScript prototype Use of 'prototype' vs. 'this' in JavaScript?