I have JSON data that I need to convert to Dictionary so I use JSONSerialization for that purpose but when I check the created dictionary, I can see that it converts the Bool to NSNumber (for property named demo)automatically
import Foundation
struct Employee: Codable {
let employeeID: Int?
let meta: Meta?
}
struct Meta: Codable {
let demo: Bool?
}
let jsonValue = """
{
"employeeID": 1,
"meta": {
"demo": true
}
}
"""
let jsonData = jsonValue.data(using: .utf8)!
if let jsonDictionary = (try? JSONSerialization.jsonObject(with: jsonData, options: .allowFragments)) as? [String: Any] {
print(jsonDictionary)
}
OUTPUT
["meta": {
demo = 1; }, "employeeID": 1]
Is there a way to avoid this Bool to NSNumber conversion or maybe convert NSNumber back to Bool using a custom logic ?
For decoding I need to convert that Dictionary to Data which I will input in JSONDecoder
If that is the case, you would use the data(withJSONObject:options:) method instead.
Below is how you would do that:
let dictionary: [String : Any] = [ "employeeID": 1,
"meta": [ "demo": true ] ]
do {
let data = try JSONSerialization.data(withJSONObject: dictionary, options: [])
let employee = try JSONDecoder().decode(Employee.self, from: data)
print(employee)
} catch {
print(error)
}
And I would think again if I really need the properties of the structs to be Optionals.
Related
I'm trying to convert an object to NSDictionary with an extension. It works fine but if the object contains an array, then the array does not convert to NSDictionary but to Json and that is not what I want. Because I try with this Dictionary to make a request post and the body accepts [String: Any].
My code:
struct Country: Codable {
let name: String
let cities: [City]
struct City: Codable {
let name: String
}
}
extension NSDictionary {
func encode<T>(_ value: T) throws -> [String: Any]? where T: Encodable {
guard let jsonData = try? JSONEncoder().encode(value) else { return nil }
return try? JSONSerialization.jsonObject(with: jsonData, options: .allowFragments) as? [String: Any]
}
}
Using:
let country = Country(name: "France", cities: [Country.City(name: "Paris"), Country.City(name: "Marseille")])
print(try! NSDictionary().encode(country))
Output:
["name": France, "cities": <__NSArrayI 0x600002926e60>(
{
name: "Paris",
},
{
name: "Marseille",
})
]
Expected output (what I want):
["name": France, "cities": [
[
"name": Paris,
],
[
"name": Marseille,
]
]
]
The output is correct since your result is NSDictionary and the output is the string representation (aka description) of NSDictionary. <__NSArrayI 0x600002926e60> is syntactic sugar.
By the way the expected output is invalid because the city names must be in double quotes.
The extension of NSDictionary makes no sense anyway. If you want to be able to call the method from everywhere declare a struct with a static method.
This is a swiftier version of your code. No allowFragments and all errors are thrown rather than being ignored.
struct DictionaryEncoder {
static func encode<T>(_ value: T) throws -> [String: Any] where T: Encodable {
let jsonData = try JSONEncoder().encode(value)
return try JSONSerialization.jsonObject(with: jsonData) as? [String: Any] ?? [:]
}
}
Copy the method and your structs into a Playground and run
let country = Country(name: "France", cities: [Country.City(name: "Paris"), Country.City(name: "Marseille")])
try! DictionaryEncoder.encode(country)
Don't print the result, look at the result area in the Playground, the output is exactly what you want.
You need
let res = try! JSONEncoder().encode(country)
print(res.prettyPrintedJSONString!)
extension Data {
var prettyPrintedJSONString: NSString? { /// NSString gives us a nice sanitized debugDescription
guard let object = try? JSONSerialization.jsonObject(with: self, options: []),
let data = try? JSONSerialization.data(withJSONObject: object, options: [.prettyPrinted]),
let prettyPrintedString = NSString(data: data, encoding: String.Encoding.utf8.rawValue) else { return nil }
return prettyPrintedString
}
}
Result
{
"name" : "France",
"cities" : [
{
"name" : "Paris"
},
{
"name" : "Marseille"
}
]
}
How to parse following json which I want to parse only few part.
```
{
"head": {
"StatusValue": 200,
"StatusText": "Success"
},
"body": {
"Data": [
{
"payer_type_id": 1,
"payer_type": "Self Pay"
},
{
"payer_type_id": 2,
"payer_type": "Corporate"
},
{
"payer_type_id": 6,
"payer_type": "Insurance"
}
],
"RecordCount": 3,
"TotalRecords": null
}
}
How to parse only data inside Data key.
Expected result should be in following format
Date = [["payer_type_id": 1,"payer_type": "Self Pay"],["payer_type_id": 2,"payer_type": "Corporate"],["payer_type_id": 6,"payer_type": "Insurance"]]
You can use Codable protocol for your parsing .
Create Your Model
struct APIRootModel : Codable {
let head : HeaderModel
let body : BodyModel
}
struct HeaderModel :Codable{
let StatusValue : Int
let StatusText : String
}
struct BodyModel : Codable{
let Data : [DataModel]
}
struct DataModel : Codable{
let payer_type_id : Int
let payer_type : String
}
Decode your json using JSONDecoder()
let decoder = JSONDecoder()
do {
let rootModel = try decoder.decode(APIRootModel.self, from: jsonData)
print(rootModel.body.data)
} catch {
print(error)
}
Use [DataModel] for your tableview datasource.
Try this:
let jsonString = "your json string here"
let dictObject = getDictionaryFromJsonString(dictString: jsonString)
let bodyDict = dictObject["body"]
let dataArray = bodyDict["Data"]
func getDictionaryFromJsonString(dictString:String)->
[String: Any] {
do {
return try JSONSerialization.jsonObject(with:
dictString.data(using: String.Encoding.utf8,
allowLossyConversion: true)!, options:
JSONSerialization.ReadingOptions.allowFragments) as!
Dictionary
} catch {
return [:]
}
}
Here the Dictionary
struct Person : Codable {
let name : String?
let city : String?
let age : Int?
}
let dic : [String : Any] =
["name":"Manna","city" : "Rangpur", "age": 18,
"name":"Munna","city" :"Dhaka","age":19,
"name":"Shaon","city" :"Rangpur","age":11,
"name":"Limon","city" :"Tangail","age":15,
"name":"Lalon","city" :"Rangpur","age":18,
"name":"Rakib","city" :"Dhaka","age":15,
"name":"Mum","city" :"Rangpur","age":18,
"name":"Man","city" :"Bogura","age":12,
"name":"Limon","city" :"Tangail","age":18]
// let manna = Person(name: "Manna", city: "Rangpur", age: 18)
// Here i want to use the dictionary
let encoder = JSONEncoder()
encoder.outputFormatting = .prettyPrinted
do {
let data = try encoder.encode(manna)
print(String(data: data, encoding: .utf8)!)
} catch {
print("error : \(error.localizedDescription)")
}
trying to encode this dictionary just like json file as an output using JSONEncoder
First of all your dictionary is wrong because dictionary doesn't contains same key.
You can present it as like array of dictionary
let dic : [[String : Any]] = [["name":"Manna", "city" : "Rangpur", "age": 18],
["name":"Munna","city" :"Dhaka","age":19,],
["name":"Shaon","city" :"Rangpur","age":11,],
["name":"Limon","city" :"Tangail","age":15,],
["name":"Lalon","city" :"Rangpur","age":18,],
["name":"Rakib","city" :"Dhaka","age":15,],
["name":"Mum","city" :"Rangpur","age":18,],
["name":"Man","city" :"Bogura","age":12,],
["name":"Limon","city" :"Tangail","age":18]]
Now you can convert this array of dictionary into JSON as like below
if let data = try? JSONSerialization.data(withJSONObject: dic, options: JSONSerialization.WritingOptions.prettyPrinted) {
print(data.count)
let json = String(data: data, encoding: String.Encoding.utf8)
print(json ?? "")
}
I am trying to send a request to an API that requires this format:
{
"inputs": [
{
"data": {
"image": {
"base64": "iVBORw0KGgoAAAIVnFT/DPAAAAAElFTkSuQmCC..."
}
}
}
]
}
This is what I tried in Swift 3:
let base64 = ["base64": "1010101..."]
let image: [String: Any] = ["image": base64]
let data: [String: Any] = ["data": image]
var input = [Dictionary<String, Any>]()
input = [data]
let jsonData = try! JSONSerialization.data(withJSONObject: input, options: .prettyPrinted)
I got an invalid request error when trying to hit the endpoint. Not surprising - when I printed it:
let jsonString = try! JSONSerialization.jsonObject(with: jsonData, options: [])
print(jsonString)
It produced a string like this:
(
{
data = {
image = {
base64 = 1010101;
};
};
}
)
For now, I am rolling my own string. It works...but it's ugly as hell and just really not tenable.
let imageAsString = "{\"inputs\": [{\"data\": {\"image\": {\"base64\": \"\(strBase64)\"}}}]}"
My other thought was that I could create a series of embedded objects: a Data object that holds a dictionary; an Image object that holds a Data object; and an Inputs object that holds an array of Data objects.
class Image {
var base64 = Dictionary<String, String>()
}
class Data {
var image = Image()
}
class Inputs {
var inputs = [Data]()
}
But initializing them all and calling JSONSerialization.data doesn't work as this takes a dictionary object.
I'm not really interested in pulling in 3rd party plugins for now. Any ideas on how to convert these nested objects into json using the native iOS libraries?
Absolutely! Using the Codable protocol and JSONEncoder in Swift 4 will do the trick:
struct ImageObj: Codable {
let base64: String
}
struct DataObj: Codable {
let image: ImageObj
}
struct InputObj: Codable {
let data: DataObj
}
struct InputsContainerObj: Codable {
let inputs: [InputObj]
}
let imageObj = ImageObj(base64: "abc123")
let dataObj = DataObj(image: imageObj)
let inputObj = InputObj(data: dataObj)
let inputsContainerObj = InputsContainerObj(inputs: [inputObj])
let encoder = JSONEncoder()
do {
let jsonData = try encoder.encode(inputsContainerObj)
let jsonString = String(data: jsonData, encoding: .utf8)!
print(jsonString) //{"inputs":[{"data":{"image":{"base64":"abc123"}}}]}
} catch _ as NSError {
}
If Swift 3 is your only option, then you will have to make JSONSerialization.data work:
let dict = ["inputs": [["data": ["image": ["base64": "abc123"]]]]]
do {
let jsonData = try JSONSerialization.data(withJSONObject: dict, options: .prettyPrinted)
let jsonString = String(data: jsonData, encoding: .utf8)!
print(jsonString)
/*
{
"inputs" : [
{
"data" : {
"image" : {
"base64" : "abc123"
}
}
}
]
}
*/
} catch _ as NSError {
}
How do you convert an array to a JSON string in swift?
Basically I have a textfield with a button embedded in it.
When button is pressed, the textfield text is added unto the testArray.
Furthermore, I want to convert this array to a JSON string.
This is what I have tried:
func addButtonPressed() {
if goalsTextField.text == "" {
// Do nothing
} else {
testArray.append(goalsTextField.text)
goalsTableView.reloadData()
saveDatatoDictionary()
}
}
func saveDatatoDictionary() {
data = NSKeyedArchiver.archivedDataWithRootObject(testArray)
newData = NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions(), error: nil) as? NSData
string = NSString(data: newData!, encoding: NSUTF8StringEncoding)
println(string)
}
I would also like to return the JSON string using my savetoDictionart() method.
As it stands you're converting it to data, then attempting to convert the data to to an object as JSON (which fails, it's not JSON) and converting that to a string, basically you have a bunch of meaningless transformations.
As long as the array contains only JSON encodable values (string, number, dictionary, array, nil) you can just use NSJSONSerialization to do it.
Instead just do the array->data->string parts:
Swift 3/4
let array = [ "one", "two" ]
func json(from object:Any) -> String? {
guard let data = try? JSONSerialization.data(withJSONObject: object, options: []) else {
return nil
}
return String(data: data, encoding: String.Encoding.utf8)
}
print("\(json(from:array as Any))")
Original Answer
let array = [ "one", "two" ]
let data = NSJSONSerialization.dataWithJSONObject(array, options: nil, error: nil)
let string = NSString(data: data!, encoding: NSUTF8StringEncoding)
although you should probably not use forced unwrapping, it gives you the right starting point.
Swift 3.0 - 4.0 version
do {
//Convert to Data
let jsonData = try JSONSerialization.data(withJSONObject: dictionaryOrArray, options: JSONSerialization.WritingOptions.prettyPrinted)
//Convert back to string. Usually only do this for debugging
if let JSONString = String(data: jsonData, encoding: String.Encoding.utf8) {
print(JSONString)
}
//In production, you usually want to try and cast as the root data structure. Here we are casting as a dictionary. If the root object is an array cast as [Any].
var json = try JSONSerialization.jsonObject(with: jsonData, options: JSONSerialization.ReadingOptions.mutableContainers) as? [String: Any]
} catch {
print(error.description)
}
The JSONSerialization.WritingOptions.prettyPrinted option gives it to the eventual consumer in an easier to read format if they were to print it out in the debugger.
Reference: Apple Documentation
The JSONSerialization.ReadingOptions.mutableContainers option lets you mutate the returned array's and/or dictionaries.
Reference for all ReadingOptions: Apple Documentation
NOTE: Swift 4 has the ability to encode and decode your objects using a new protocol. Here is Apples Documentation, and a quick tutorial for a starting example.
If you're already using SwiftyJSON:
https://github.com/SwiftyJSON/SwiftyJSON
You can do this:
// this works with dictionaries too
let paramsDictionary = [
"title": "foo",
"description": "bar"
]
let paramsArray = [ "one", "two" ]
let paramsJSON = JSON(paramsArray)
let paramsString = paramsJSON.rawString(encoding: NSUTF8StringEncoding, options: nil)
SWIFT 3 UPDATE
let paramsJSON = JSON(paramsArray)
let paramsString = paramsJSON.rawString(String.Encoding.utf8, options: JSONSerialization.WritingOptions.prettyPrinted)!
JSON strings, which are good for transport, don't come up often because you can JSON encode an HTTP body. But one potential use-case for JSON stringify is Multipart Post, which AlamoFire nows supports.
How to convert array to json String in swift 2.3
var yourString : String = ""
do
{
if let postData : NSData = try NSJSONSerialization.dataWithJSONObject(yourArray, options: NSJSONWritingOptions.PrettyPrinted)
{
yourString = NSString(data: postData, encoding: NSUTF8StringEncoding)! as String
}
}
catch
{
print(error)
}
And now you can use yourSting as JSON string..
Swift 5
This generic extension will convert an array of objects to a JSON string from which it can either be:
saved to the App's Documents Directory (iOS/MacOS)
output directly to a file on the Desktop (MacOS)
.
extension JSONEncoder {
static func encode<T: Encodable>(from data: T) {
do {
let jsonEncoder = JSONEncoder()
jsonEncoder.outputFormatting = .prettyPrinted
let json = try jsonEncoder.encode(data)
let jsonString = String(data: json, encoding: .utf8)
// iOS/Mac: Save to the App's documents directory
saveToDocumentDirectory(jsonString)
// Mac: Output to file on the user's Desktop
saveToDesktop(jsonString)
} catch {
print(error.localizedDescription)
}
}
static private func saveToDocumentDirectory(_ jsonString: String?) {
guard let path = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask).first else { return }
let fileURL = path.appendingPathComponent("Output.json")
do {
try jsonString?.write(to: fileURL, atomically: true, encoding: .utf8)
} catch {
print(error.localizedDescription)
}
}
static private func saveToDesktop(_ jsonString: String?) {
let homeURL = FileManager.default.homeDirectoryForCurrentUser
let desktopURL = homeURL.appendingPathComponent("Desktop")
let fileURL = desktopURL.appendingPathComponent("Output.json")
do {
try jsonString?.write(to: fileURL, atomically: true, encoding: .utf8)
} catch {
print(error.localizedDescription)
}
}
}
Example:
struct Person: Codable {
var name: String
var pets: [Pet]
}
struct Pet: Codable {
var type: String
}
extension Person {
static func sampleData() -> [Person] {
[
Person(name: "Adam", pets: []),
Person(name: "Jane", pets: [
Pet(type: "Cat")
]),
Person(name: "Robert", pets: [
Pet(type: "Cat"),
Pet(type: "Rabbit")
])
]
}
}
Usage:
JSONEncoder.encode(from: Person.sampleData())
Output:
This will create the following correctly formatted Output.json file:
[
{
"name" : "Adam",
"pets" : [
]
},
{
"name" : "Jane",
"pets" : [
{
"type" : "Cat"
}
]
},
{
"name" : "Robert",
"pets" : [
{
"type" : "Cat"
},
{
"type" : "Rabbit"
}
]
}
]
SWIFT 2.0
var tempJson : NSString = ""
do {
let arrJson = try NSJSONSerialization.dataWithJSONObject(arrInvitationList, options: NSJSONWritingOptions.PrettyPrinted)
let string = NSString(data: arrJson, encoding: NSUTF8StringEncoding)
tempJson = string! as NSString
}catch let error as NSError{
print(error.description)
}
NOTE:- use tempJson variable when you want to use.
extension Array where Element: Encodable {
func asArrayDictionary() throws -> [[String: Any]] {
var data: [[String: Any]] = []
for element in self {
data.append(try element.asDictionary())
}
return data
}
}
extension Encodable {
func asDictionary() throws -> [String: Any] {
let data = try JSONEncoder().encode(self)
guard let dictionary = try JSONSerialization.jsonObject(with: data, options: .allowFragments) as? [String: Any] else {
throw NSError()
}
return dictionary
}
}
If you're using Codable protocols in your models these extensions might be helpful for getting dictionary representation (Swift 4)
Hint: To convert an NSArray containing JSON compatible objects to an NSData object containing a JSON document, use the appropriate method of NSJSONSerialization. JSONObjectWithData is not it.
Hint 2: You rarely want that data as a string; only for debugging purposes.
For Swift 4.2, that code still works fine
var mnemonic: [String] = ["abandon", "amount", "liar", "buyer"]
var myJsonString = ""
do {
let data = try JSONSerialization.data(withJSONObject:mnemonic, options: .prettyPrinted)
myJsonString = NSString(data: data, encoding: String.Encoding.utf8.rawValue) as! String
} catch {
print(error.localizedDescription)
}
return myJsonString
Swift 5
Make sure your object confirm Codable.
Swift's default variable types like Int, String, Double and ..., all are Codable that means we can convert theme to Data and vice versa.
For example, let's convert array of Int to String Base64
let array = [1, 2, 3]
let data = try? JSONEncoder().encode(array)
nsManagedObject.array = data?.base64EncodedString()
Make sure your NSManaged variable type is String in core data schema editor and custom class if your using custom class for core data objects.
let's convert back base64 string to array:
var getArray: [Int] {
guard let array = array else { return [] }
guard let data = Data(base64Encoded: array) else { return [] }
guard let val = try? JSONDecoder().decode([Int].self, from: data) else { return [] }
return val
}
Do not convert your own object to Base64 and store as String in CoreData and vice versa because we have something that named Relation in CoreData (databases).
For Swift 3.0 you have to use this:
var postString = ""
do {
let data = try JSONSerialization.data(withJSONObject: self.arrayNParcel, options: .prettyPrinted)
let string1:String = NSString(data: data, encoding: String.Encoding.utf8.rawValue) as! String
postString = "arrayData=\(string1)&user_id=\(userId)&markupSrcReport=\(markup)"
} catch {
print(error.localizedDescription)
}
request.httpBody = postString.data(using: .utf8)
100% working TESTED
You can try this.
func convertToJSONString(value: AnyObject) -> String? {
if JSONSerialization.isValidJSONObject(value) {
do{
let data = try JSONSerialization.data(withJSONObject: value, options: [])
if let string = NSString(data: data, encoding: String.Encoding.utf8.rawValue) {
return string as String
}
}catch{
}
}
return nil
}