Swift 3 : How to convert struct to Parameters

Question

I have a struct as follows

struct UserInfo
{
    var userId : Int
    var firstName : String
    var lastName : String
}

How do I serialize an instance of UserInfo to type Parameters?

var user = UserInfo(userId: 1, firstName: "John", lastName: "Skew")

// Convert user to Parameters for Alamofire
Alamofire.request("https://httpbin.org/post", parameters: parameters)

Answer 1

Just implement a dictionaryRepresentation computed variable or function:

struct UserInfo {
    var userId : Int

    var firstName : String
    var lastName : String

    var dictionaryRepresentation: [String: Any] {
        return [
            "userId" : userId,
            "firstName" : firstName,
            "lastName" : lastName
        ]
    }
}

Usage:

var user = UserInfo(userId: 1, firstName: "John", lastName: "Skew")
let userDict = user.dictionaryRepresentation

Answer 2

You could use CodableFirebase library. Although it's main purpose is to use it with Firebase Realtime Database and Firestore, it actually does what you need - converts the value into dictionary [String: Any].

Your model would look the following:

struct UserInfo: Codable {
    var userId : Int
    var firstName : String
    var lastName : String
}

And then you would convert it to dictionary in the following way:

import CodableFirebase

let model: UserInfo // here you will create an instance of UserInfo
let dict: [String: Any] = try! FirestoreEncoder().encode(model)