Swift decode nested dictionary
Swift decode nested dictionary. io), let Swift generate the methods to decode it, and then pick off the pieces that you want in your final data model: Jun 18, 2017 · On 23 Jun 2017, at 03:45, Jon Shier via swift-users >> <swift-users@swift. So this field should be optional as well in your model. decode([String:JSON]. encode(model) let decoded = try? JSONDecoder(). Then it will iterate through ALL entries in it. May 30, 2020 · Make advance use of the Swift Decodable protocol and Swift generic concept to decode and flatten a JSON with dynamic keys. Nov 22, 2023 · Working with nested JSON data is a common task when developing iOS applications. JSON data received from a server or from a local file. May 23, 2018 · I found other questions about iterating through dictionaries like Iterating Through a Dictionary in Swift but these examples are basic arrays and not multi-nested dictionaries using Swift's new protocols. The parent object can instead be decoded as a dictionary with String or Int keys, depending on the kind of keys the JSON data uses. First of all, you need to be aware of the optional fields. In the truly general case, you can throw in some json, get back a generic dictionary of [String: Any], and cast as needed. We need to take extra steps to determine the correct type first. encode(to: encoder) var container = encoder. singleValueContainer() let meta = try container. Decode JSON and visualize data in your iOS apps with ease. all other Swift dictionaries with non-String or non-Int Key types will be encoded into an array of alternating keys and values. Aug 19, 2024 · Learn how to parse JSON in Swift without any external dependencies. . 1. 1 thanks to new functionality being added, and I expect even greater things to come in the future. Here is how we could transfer this data into a Swift data type: A type that can be decoded from a JSON dictionary-decoder. Mar 18, 2022 · How to Decode Nested dictionary with nested arrays using Swift Decodable property? 1 Swift JSONDecoder handling Dictionary of Array of Dictionary Dec 22, 2017 · No they don't. Th Mar 22, 2018 · Swift Codable - decode nested dictionary. In Swift, we can easily decode this JSON data into Swift dictionaries using the JSONDecoder class. The Codable protocol in Swift can handle such nested structures with ease, which is one of its major advantages. Apr 30, 2024 · Codable was one of the cornerstone features of Swift 4. 9. I want to make one function in my swift project that converts String to Dictionary json format but I got one error: Cannot convert expression's type (@lvalue NSData,options:IntegerLitralConverti Jan 25, 2018 · Here, we create the object variable and loop through the colours we just got from our API call and cast that to a temporary dictionary so we can then parse the results to the correct types Mar 22, 2021 · I’ve got JSON like this: { "states" : [ "C", "A", "B", "Sink", ], "symbols" : [ "c", "a Sep 3, 2020 · Dictionary itself specifically treats Int and String keys differently from the rest. Aug 13, 2020 · I think what you are looking for is a dictionary where its values are dictionaries. 570. Adding nested dictionary causes Jun 7, 2021 · As mentioned in that thread, you should probably decode to a [String: SoundModel] first, and then recreate a list of SubSoundModels from that dictionary once you have direct access to the dynamic keys. However, when a type is dynamic, it’s impossible to know it before parsing the JSON data. I want to be able to: 1. 0, bringing with it incredibly smooth conversion between Swift data types and JSON. Oct 10, 2017 · It's pretty simple to decode, like so: let data = rawJson. I have a struct like this: struct GameCharacter : Codable { var name : String var weapons : [Weapon] enum CodingKeys : Stri Jan 6, 2022 · I have a JSON result from the server that looks like the following: let json = """ { "type": "rating", "data": { " Apr 30, 2018 · In this case I recommend to decode the JSON as dictionaries [String:[String]] struct WeekendMenu: Decodable { private enum CodingKeys : String, CodingKey { case brunch = "Brunch", dinner = "Dinner" } let brunch: [String:[String]] let dinner: [String:[String]] } Enumerate the dictionaries, sort the keys to get the same order Jun 10, 2020 · Good while you are learning the ropes. So my question is this: Am I missing something? Have I got this all wrong and there's a super-easy way to either (a) send JSON (instead of a dictionary) in the REQUEST or (b) convert an object automatically to a Sep 27, 2023 · When working with web APIs, it’s common to receive responses in JSON format. Swift Decoding nested JSON. Swift 4 Decodable: struct from nested array. Adopting these protocols lets implementations of the Encoder and Decoder protocols take your data and encode or decode it to and from an external representation such as JSON or property list. This decreases the control that authors have over their Codable models, and can require the creation of unnecessary boilerplate objects. Use JSONDecoder to unpack nested JSON values. org>> wrote: I’m sorry, are you complaining about my use of Codable instead of more precisely referring to the JSON endcode/decode functionality based on it in Foundation, or are you honestly trying to say that said functionality was never Sep 14, 2020 · The key idea is to check if there's a nested dictionary or a nested array inside the json and then iterate Parsing objects in Json array as a dictionary Swift. Context: I am Jul 17, 2017 · Let’s decode some decodables, from JSON to Swift. Feb 24, 2020 · Introduction Today, decoding JSON using JSONDecoder with a synthesized Codable implemenation requires that your object graph has a one-to-one mapping to the object graph of the source JSON. 2. Jul 20, 2017 · Swift Codable - decode nested dictionary. Firstly, convert JSON into an object like this, it will make it easier if you update with more fields: struct Person: Codable { var firstName: String var lastName: String } Nov 29, 2020 · I have a JSON format that I'm trying to parse with JSONDecoder but due to the way the JSON is structured, I can't figure out how to do it. My JSON data result looks like this: SWIFT "Expected to decode Dictionary<String, Any> but Aug 8, 2018 · I am very new to Swift and I'm attempting to decode the following dictionary with nested values ` Data Optional(Dictionary. The nested JSON objects require a Decodable Swift type. utf8) let decoder = JSONDecoder() let users = try! decoder. I have tried with multiple structures and c Dec 12, 2018 · These structs don't decode all keys, but it's a starting point. Aug 20, 2020 · I'm new to Swift 5. Swift Codable - decode nested dictionary. struct Directions: Decodable { let status: String let routes: [Route] } struct Route: Decodable { let summary: String let legs: [Leg] } struct Leg: Decodable { let duration : TextValue let distance : TextValue let endAddress : String let Feb 16, 2019 · Intent: Receive cryptocurrency price data via Coinmarketcap API, decode it into custom structs in SWIFT and potentially store that data in a database (either CoreData or SQLite). Apr 28, 2020 · Swift Decodable JSON dictionary with heterogeneous array. Apr 4, 2024 · Working with dynamic types complicates decoding data in Swift using the Codable protocols because a decoder must know the concrete Swift type to decode data. decode([User]. data(using: . I know the top level keys (objects) but those may or may not be present for each fetch. Modified 5 years, 5 months ago. Jan 31, 2018 · JSONEncoder(). You must use a concrete generic type for your dictionary (e. Keys([AnyHashable("playesOnline")])) Optional(<__NSSingleObjectArrayI Jun 17, 2017 · Found This Link - Go down to inheritance section. Apr 15, 2022 · Yes, your declaration of series is an array of Series, so calling the decoder is trying to decode an array Series items. self, from: data!) But what if the JSON looks like this, where the top level is a dictionary and need to fetch the array of users: Apr 23, 2018 · Trying to write a simple Swift 4. Sep 23, 2023 · To decode JSON data in Swift, you need two things: A Swift data structure (struct or class) that conforms to the Codable protocol. var Mar 24, 2023 · How to decode a nested JSON struct with Swift Decodable protocol? 177. Each key within the objects (and the ones nested inside those) is unknown. [String: Any] or [Any]). I suggest Use an enum named JSONValue which has 5 to 6 cases for all Int, String, Double, Array, Dictionary cases. If the entry is another dictionary it will then open that one and iterate through all of its entries and so on. JSON parsing in Swift is a common thing to do. Unfortunately, mixing these approaches can be tricky. Iterate through the JSON and extract only the symbols from the CMC API. You may want to check out the dictionary tutorial / help here or here. io Its a fast way to create models, does all the checks for you, and creates models in couple different languages. How to decode a property with type of JSON dictionary in Swift [45] decodable protocol. You can also decode into concrete types you know the shape of. Apr 1, 2024 · However, this method requires creating Swift model types that match the JSON data structure you need to decode. The enclosing container of the token dictionary is an array. var aDictionary = [String: String]() or Jun 17, 2017 · Let's say I have Customer data type which contains a metadata property that can contains any JSON dictionary in the customer object struct Customer { let id: String let email: String let met Jun 14, 2017 · Another approach is to create an intermediate model that closely matches the JSON (with the help of a tool like quicktype. then you can write JSONs in a type-safe way. Aug 12, 2015 · True. This will work with (almost) infinitely nested dictionaries. Sometimes, you might want to avoid creating extra Swift types if you only need to read some of the information in the JSON data locally. To flatten it, use keyed and unkeyed containers. May 18, 2023 · As you can see, the JSON structure is a nested combination of arrays and dictionaries (objects), which is a common structure for JSON data. override func encode(to encoder: Encoder) throws { try super. Apr 2, 2024 · Nested JSON can be decoded in Swift using Decodable and JSONDecoder. Swift 4 JSON Parsing (Expected to decode Dec 3, 2018 · Unfortunately you cannot use encode or decode on generic types containing Any (e. g. That is, go through all of the object properties and map them as a dictionary. Anyway I will post both options: extension Encodable { // this would try to encode an encodable type and decode it into an a dictionary var dictionary: [String: Any] { guard let data = try? Oct 1, 2021 · However, how do I initialize this dictionary with a nested array? I tried something like // here is the issue - what should the searchResults structure look like? // to properly store the response var searchResults: [String: AnyObject] = [String: AnyObject]() I have a class in Swift whose structure resembles this: class MyClass { var name: String var data: String } Which could be initialised where data contains a JSON object encoded as a String. To declare an empty dictionary, you will need to pass the types to the dictionary and immediatley create it. Jan 31, 2024 · In Swift, converting a JSON string to a dictionary typically involves using the JSONSerialization class from the Foundation framework. If you then want to extract one of the associated values, it's most common to offer those as computed properties on the enum type itself. If an entry is a string however you can then do whatever you want to do Mar 25, 2021 · "Expected to decode Array but found a dictionary instead. Any does not conform to protocols Encodable nor Decodable and Swift doesn't know how to encode/decode it. Decoding strings The JSONStringDecodable protocol is a bridge that allows string-convertible types to opt into an automatic string-based JSONDecodable conformance. But I would rather go the standard library's way to provide an encoder/decoder object. How to Decode Nested dictionary with nested arrays using Swift Decodable property? 1. May 2, 2020 · I have been searching all the internet to correctly parse the following plist in swift but I cannot manage to find the correct way to do it. Apr 3, 2024 · Therefore, the simplest way to decode JSON data with dynamic keys is to transform it into a Swift dictionary. Ask Question Asked 6 years, 9 months ago. You have to insert an intermediate nestedUnkeyedContainer Aug 19, 2024 · Swift Aug 19, 2024 Aug 19, 2024 • 6 min read JSON Parsing in Swift explained with code examples. 0. self) // e. self) try container. Using Decodable to decode array of nested Jul 12, 2022 · Swift has some nice facilities for working with json. The function will "open" a dictionary. It then got even better in Swift 4. To parse nested JSON objects, you create Swift types that match the JSON data’s nesting structure. decode(Model. Jun 14, 2018 · You have several issues. But when you have lots of json to parse and create models I prefer tools like - app. Here’s a step-by-step explanation and example: Step 1: Import Foundation Jan 31, 2024 · In Swift, converting a JSON string to a dictionary typically involves using the JSONSerialization class from the Foundation framework. Almost every app decodes JSON to show data in a visualized way. Here’s a step-by-step explanation and example: Step 1: Import Foundation May 27, 2018 · It works like that: 1) decode json, check properties 2) encode obj (1) back to string 3) decode json( 2) check properties 4) encode obj (3) to second string 5) check strings from 2 and 4 are equal Of course whole test ends with success. employeeID) } May 9, 2019 · I have a nested json structure. 4. Please help. In this blog post, we will explore the steps required to decode JSON into Swift dictionaries. Jul 20, 2017 · There is no built in way to do that. Oct 26, 2021 · Using Codable to encode/decode JSON data. Mar 16, 2021 · - as a Codable type can encode into anything (including another dictionary), Swift will encode Swift dictionaries into json/plist dictionaries only when the Key type is String or Int. [String: String]). " Swift - Parse array in nested JSON Object not working. Jan 29, 2021 · First of all I assume that your decoder has an appropriate date decoding strategy to be able to decode the ISO8601 strings to Date. But the request needs to be manually coded. As answered above if you have no performance issues then you can accept the JSONEncoder + JSONSerialization implementation. If you want more help, you should read more about the new Codable protocol. To support both encoding and decoding, declare conformance to Codable , which combines the Encodable and Decodable protocols. In Swift, the Codable protocol simplifies the process of decoding JSON data into native Swift objects. Here's the format of the JSON. Viewed 5k times 5 Lets say I have a dictionary Mar 16, 2018 · init(from decoder: Decoder) throws { let container = decoder. Step 1: Define a Codable structure. quicktype. Oct 11, 2021 · How to convert the given dictionary into a JSON Object containing a JSON Array In Swift? Apr 15, 2024 · Parse JSON in Swift without Codable [Arrays and Dictionaries] Decoding nested JSON objects using nested Swift types. container(keyedBy: CodingKeys. I propose that we add support for Encoding and Decoding nested JSON Dec 19, 2021 · You're on the right track by creating an enum to represent the possible types in the array. look for keys in meta and then chose for example a case of this enum } This is just a summary of the previous answers I think, but in my understanding it should be enough to solve your issue. In contrast to JSONSerialization which understands JSON types such as strings and numbers and arrays and dictionaries, JSONDecoder instantiates anything that’s Decodable — that’s how you can decode JSON directly to your own types. 1 using Codable to parse json. This article is part of the Parsing JSON in Swift series. You would need a wrapper since with Encodable protocol to know which item is which to be able to encode it easier. If keys and struct members have the same name you don't need to specify CodingKeys. self, from: encoded!) It won't really work if you set params: [String: Any] because the encoders/decoders don't know how to encode/decode Any, but they can do it for the primitive types. Jul 22, 2022 · I recently built DeepCodable, a package to encode and decode arbitrarily-nested data into flat Swift structs, by defining the coding paths with a result builder. From your attached JSON, it's clearly seen that uuid inside players_loop can be null. 3 and having trouble retrieving my nested JSON data. In particular, dictionaries with Int or String keys are treated as JSON objects, while all other dictionaries are treated as arrays of key-value pairs. I personally have been wanting something like this for a long time when interacting with third-party APIs, so I decided to build it. org <mailto:swift-users@swift. encode(employeeID, forKey: . Note that the decode() method needs to know the type of the result instance. tsuayb lshkcilbu nxhmuw nhqdqy wqkiiw apw fmcuyh ghlkq yka hsewnxi