【Swift】 JSONEncoder / JSONDecorder の基本的な使い方

サンプルから。

struct GroceryProduct: Codable {
  var name: String
  var points: Int
  var description: String?
}

let pear = GroceryProduct(name: "Pear", points: 250, description: "A ripe pear.")

let encoder = JSONEncoder()
encoder.outputFormatting = .prettyPrinted

let data = try encoder.encode(pear)
print(String(data: data, encoding: .utf8)!)

/*
{
  "name" : "Pear",
  "points" : 250,
  "description" : "A ripe pear."
}
*/

struct GroceryProduct: Codable {
  var name: String
  var points: Int
  var description: String?
}

let json = """
{
    "name": "Durian",
    "points": 600,
    "description": "A fruit with a distinctive scent."
}
""".data(using: .utf8)!

let decoder = JSONDecoder()
let product = try decoder.decode(GroceryProduct.self, from: json)

print(product.name) 

// Prints "Durian"

要するにこういうことです。

🤔 参考