在Swift中使用JSONDecoder解析JSON时将NULL值转换为默认字符串

struct MyModel: Codable {
    let name: String
    let age: Int
    let description: String
    
    enum CodingKeys: String, CodingKey {
        case name
        case age
        case description
    }
    
    init(from decoder: Decoder) throws {
        let container = try decoder.container(keyedBy: CodingKeys.self)
        
        name = try container.decodeIfPresent(String.self, forKey: .name) ?? "Default Name"
        age = try container.decodeIfPresent(Int.self, forKey: .age) ?? 0
        description = try container.decodeIfPresent(String.self, forKey: .description) ?? "Default Description"
    }
}

let json = """
{
    "name": "John",
    "age": null,
    "description": null
}
"""

let jsonData = json.data(using: .utf8)!

do {
    let decoder = JSONDecoder()
    let myModel = try decoder.decode(MyModel.self, from: jsonData)
    print(myModel.name) // Output: John
    print(myModel.age) // Output: 0
    print(myModel.description) // Output: Default Description
} catch {
    print("Error: \(error)")
}