Question 1

What is the Codable protocol in Swift?

Accepted Answer

Codable is a typealias combining Encodable and Decodable. It enables serialization and deserialization of Swift structures to/from JSON or other formats. It's the standard mechanism for handling JSON in iOS without external frameworks.

Question 2

What is the difference between Encodable and Decodable?

Accepted Answer

Encodable serializes a Swift instance into JSON data (object to JSON). Decodable performs the reverse operation, converting JSON into a Swift instance. These protocols are orthogonal: a struct can implement one, the other, or both as needed.

Question 3

What is the purpose of the CodingKeys enum during JSON decoding?

Accepted Answer

CodingKeys maps Swift properties to actual JSON keys. It handles naming mismatches between Swift code (camelCase) and JSON (snake_case). Without CodingKeys, property names must exactly match JSON keys.

Codable & JSON Parsing

What is the Codable protocol in Swift?

Odpowiedź

What is the difference between Encodable and Decodable?

Odpowiedź

What is the purpose of the CodingKeys enum during JSON decoding?

Odpowiedź

How to create a JSONDecoder instance to decode JSON?

What does JSONEncoder.encode() return after successful serialization?

Inne tematy rekrutacyjne iOS

Swift Basics

Swift Language Essentials

UIKit Fundamentals

UIViewController Lifecycle

UserDefaults & Keychain

Application Lifecycle

Auto Layout & Constraints

UITableView & UICollectionView

SwiftUI Basics

SwiftUI State Management

SwiftUI Navigation

Networking & URLSession

Core Data

Protocol Oriented Programming

MVVM Architecture

Push Notifications

Unit Testing & XCTest

UI Testing

Xcode & Build System

Swift Package Manager

Memory Management & ARC

Combine Framework

Concurrency & async/await

iOS Design Patterns

Performance Optimization

Security & Encryption

SwiftUI Advanced

iOS Application Architecture

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