Help with JSON and JavaScript...I have the other files but I only need help on t

Question

Help with JSON and JavaScript...I have the other files but I only need help on this. Let me know if you want to see the rest.

1. Add code to the getContacts method that creates a function named reviver. Code the reviver method so it adds dashes back to regular phone numbers (7 characters), phone numbers with area codes (10 characters), and phone numbers with 1 + area code (11 characters). Then, use the reviver function with the parse method.

2. add code to the setContacts method that creates a function named replacer. Code the replacer function so it strips all non-numeric characters from the phone number value. Then, use the replacer function with the stringify method.

"use strict";

var storage = {
keyContacts: "contacts_1",
getContacts: function() {   
// get string from local storage
var storageString = localStorage.getItem(this.keyContacts) || null;
  
// convert string to JavaScript object and return, or return empty array if string is null
return JSON.parse(storageString) || [];
},
setContacts: function(value) {
// convert JavaScript object to string
var storageString = JSON.stringify(value);
  
// store string in local storage
localStorage.setItem(this.keyContacts, storageString);
},
clearContacts: function() {
localStorage.setItem(this.keyContacts, "");
}
};

Explanation / Answer

var Types = {}; function MyClass(foo, bar) { this._foo = foo; this._bar = bar; } Types.MyClass = MyClass; MyClass.prototype.getFoo = function() { return this._foo; } // Method which will provide a JSON.stringifiable object MyClass.prototype.toJSON = function() { return { __type: 'MyClass', foo: this._foo, bar: this._bar }; }; // Method that can deserialize JSON into an instance MyClass.revive = function(data) { // TODO: do basic validation return new MyClass(data.foo, data.bar); }; var instance = new MyClass('blah', 'blah'); // JSON obtained by stringifying an instance var json = JSON.stringify(instance); // "{"__type":"MyClass","foo":"blah","bar":"blah"}"; var obj = JSON.parse(json, function(key, value) { return key === '' && value.hasOwnProperty('__type') ? Types[value.__type].revive(value) : this[key]; }); obj.getFoo(); // blah

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