Hey guys so I create a NSMutableArray send it to my mysql server convert it to base64, then when the app reads the data, it decodes the base64 code into a string format. Now im trying to convert the string back into an NSMutableArray. I cant seem to get it work heres the code that converts it to a string.
let string = String(data: (Data(base64Encoded:((data?.value(forKey: "14112017") as! NSArray)[0] as! NSDictionary)["data"] as! String)!), encoding: .utf8)!
So the answer to my question ended up converting my array to a JSONstring first which I did by using:
let jsonData: Data? = try? JSONSerialization.data(withJSONObject: UniversalArray)
let jsonString = String(data: jsonData!, encoding: .utf8)
then when retreiving it I get back my jsonString, however it has "\" which I replace using:
let cleanJsonString = myData.replacingOccurrences(of: "\\", with: "")
then to finally finish it off I just send this cleanJsonString to this function:
func convertToDictionary(text: String) -> Any? {
if let data = text.data(using: .utf8) {
do {
return try JSONSerialization.jsonObject(with: data, options: [])
} catch {
print(error.localizedDescription)
}
}
return nil
}
when calling this function I used this:
let array = convertToDictionary(text: myMutableArray) as? [AnyObject]
Thanks everyone for the amazing support, heres the answer to this bogus mess I created.
There are 2 parts to this: Serializing your array for transmission to your server, and then deserializing it from the server.
We need to see the code you use to serialize your array first. (The code that converts it to a string.) Based on what you post, it appears to be in JSON format. If so you may be able to skip the base64 encoding step, depending on what you're doing with the data. JSON is a good format for transmission to remote servers. You don't typically base64 encode JSON before transmission.
If you are receiving JSON that was then base64 encoded, you'll need to un-encode it back to data, and then use the JSONSerializer class to convert the JSON back to objects like arrays or dictionaries:
let data = Data(base64Encoded: base64DataFromServer)
guard let object = try? JSONSerialization.jsonObject(with: data) else {
return nil
}
(Note that the JSON you posted contains a dictionary as the top-level object, not an array.)
Related
I am new to the swift language. I am trying to fetching some data from an API call and response to that API is "{"status":1,"msg":"Please enter Mobile number"}"
I have the above response in a string How can I convert this string to JSONObject and then parse it and get status value?
I am an android developer we have evaluate expression while debugging code is there some like in Xcode so I can execute some code run time
I suggest use SwiftyJson library .
first create a model from your json using http://jsoncafe.com
you can parse data and model it using the following code
let json = JSON(response)
let message = Message(fromJson: json )
then you have access to your variable => message.status
JSONSerialization is the tool you are looking for. It handles converting JSON into objects, and objects into JSON. If you receive a JSON string represented as Data, you can pass it into JSONSerialization.jsonObject(with:options:)
If you are wanting to convert Data into an object:
//Where 'data' is the data received from the API call
guard let jsonObject = try? (JSONSerialization.jsonObject(with: data, options: []) as! [String:Any]) else {
return
}
let status = jsonObject["status"] as! Int
let message = jsonObject["msg"] as! String
If you are wanting to convert String into an object:
//Where 'string' is the JSON as a String
guard let jsonObject = try? (JSONSerialization.jsonObject(with: string.data(using: .utf8), options: []) as! [String:Any]) else {
return
}
let status = jsonObject["status"] as! Int
let message = jsonObject["msg"] as! String
Source: https://developer.apple.com/documentation/foundation/jsonserialization
I am very confused on this one. I had been thinking it was something wrong with my server, but after testing it seems as though using Data(base64encoded: data) is producing nil even though the data is there and is in fact base64encoded.
I have tried everything I can think of and nothing is working. Here is the code I am using and the output...
do {
print("DATA as a string: ", String(data: data!, encoding: .utf8) ?? "NONE AVAILABLE")
let decodedData = Data(base64encoded: data!, options: .ignoreUnknownCharacters)
print("DECODED DATA: ")
print(decodedData as Any)
let apiResponse = try JSONDecoder().decode(ApiConnectionResponse.self, from: decodedData!)
completion(.success(apiResponse))
} catch {
completion(.failure(error))
}
The output from that is...
Data as string:
eyJzdWNjZXNzIjoiZmFsc2UiLCJlcnJvciI6Im1vYmlsZV9waW5fY29ubmVjdDogaW52YWxpZCBvciBleHBpcmVkIn0.
DECODED DATA: nil
So the String is a legit base64encoded string, it decodes to
{"success":"false","error":"mobile_pin_connect: invalid or expired"}
However the decoded data is nil. I don't understand, how can it be nil when the string is a base64encoded string and is not nil.
I have even tried forcing the string in there like so...
let decodedData = Data(base64encoded: String(data: data!, encoding: .utf8))
Still no luck. It is throwing a fatal error, and I can see in the section at the bottom of Xcode that the data is in fact "(Data?) 92 bytes" What I can't figure out is why it is nil after running through Data()...
Any help would be greatly appreciated, I am really lost and can't figure out why I can make the string, but not the data.
The end result of this is, I need to get JSONDecoder().decode to work with the reply from the server, I think I can get that part done, if I can figure out why it is nil after the data call. Thank you.
You need to check your data length, divide by 3 and in case the result is not zero add one or two bytes (65) = equal sign for padding your data. Try like this:
let decodedData = Data(base64Encoded: data + .init(repeating: 65, count: data.count % 3))
extension Data {
var base64encodedDataPadded: Data {
let data = last == 46 ? dropLast() : self
return data + .init(repeating: 65, count: data.count % 3)
}
}
Playground testing:
let data = Data("eyJzdWNjZXNzIjoiZmFsc2UiLCJlcnJvciI6Im1vYmlsZV9waW5fY29ubmVjdDogaW52YWxpZCBvciBleHBpcmVkIn0.".utf8)
let decodedData = Data(base64Encoded: data.base64encodedDataPadded)!
print(String(data: decodedData, encoding: .utf8)!) // "{"success":"false","error":"mobile_pin_connect: invalid or expired"}"
I guess the encoded data is wrong.
let originalString = """
{"success":"false","error":"mobile_pin_connect: invalid or expired"}
"""
let base64string = originalString.data(using: .utf8)?.base64EncodedString()
print(base64string)
let base64EncodedData = originalString.data(using: .utf8)?.base64EncodedData()
let base64EncodedString = String(data: base64EncodedData!, encoding: .utf8)
print(base64EncodedString)
let decodedData = Data(base64Encoded: base64EncodedData!)
let decodedString = String(data: decodedData!, encoding: .utf8)
print(decodedString)
The log is as below:
Optional("eyJzdWNjZXNzIjoiZmFsc2UiLCJlcnJvciI6Im1vYmlsZV9waW5fY29ubmVjdDogaW52YWxpZCBvciBleHBpcmVkIn0=")
Optional("eyJzdWNjZXNzIjoiZmFsc2UiLCJlcnJvciI6Im1vYmlsZV9waW5fY29ubmVjdDogaW52YWxpZCBvciBleHBpcmVkIn0=")
Optional("{\"success\":\"false\",\"error\":\"mobile_pin_connect: invalid or expired\"}")
According to the base64 specification, . is not a valid character. = is the appropriate character for padding.
https://en.wikipedia.org/wiki/Base64
You show your base64 string as having a period and a newline at the end. That doesn't look correct. An online base64 decoder decodes it with or without that final period and newline, but Swift probably chokes with it in place.
As a Swift newcomer, I am very confused about how to parse some JSON data obtained from an API. I am able to get the JSON data from the api using an alamofire request. At this point, I think I have an NSDictionary object, JSON as print(JSON) logs to console a good deal of JSON.
if let result = response.result.value {
let JSON = result as! NSDictionary
print("this is what JSON is")
print(JSON)
My question is, first, is JSON in fact an NSDictionary. Second, how would I access a value in the JSON. Do I need to first convert this to a data object. Or how do I get at the nested data.
For example, let's say the JSON looks like this:
{
"contact": {
"first": "Bob",
"second":"Jones"
}
}
I came across this code on SO:
let data = JSON(data: JSON)
print("data\(data["contact"]["first"])")
But it throws an error. I have swiftyJSON installed but happy for solution with or without it.
Thanks in advance for any suggestions
Can you try
if let result = response.result.value as? [String:Any] {
if let contact = result["contact"] as? [String:Any] {
if let first = contact["first"] as? String {
print(first)
}
}
}
also this
let data = JSON(data: JSON)
gives error because parameter should be of type Data not Dictionary
I would prefer to return Data from Alamofire request and use Decodable to parse it and convert to required model
TRY THIS!
if let data = response.data {
let jsonData = JSON(data: data)
print("data : \(jsonData["contact"]["first"].string)")
}
Swift4 introduce amazing Codable protocol.
Using Codable, we can model JSONObject or PropertyList file into equivalent Struct or Classes by writing very few lines of code.
There are many online tool available which creates model class from you JSON
(http://www.json4swift.com/)
Example
let decoder = JSONDecoder()
let parsedObject = try decoder.decode(Class.self, from: data)
You can find detail at below link:
https://developer.apple.com/documentation/foundation/archives_and_serialization/encoding_and_decoding_custom_types
I want to array string to base64 and then back to the string
I try the following
let array = [[1,2,"preved"], [3,4,"hola"], [5,6,"poka"]]
let encodedData = NSKeyedArchiver.archivedData(withRootObject: array)
let base64String = encodedData.base64EncodedString()
let data = Data(base64Encoded: base64String)
let decodedData = NSString(data: data!, encoding: String.Encoding.utf8.rawValue)
print(decodedData)
problem is that decoded data prints back nil
What am I doing wrong ?
When using NSKeyedArchivercoder , NSKeyedUnarchiver decoder should be also used:
NSKeyedArchiver, a concrete subclass of NSCoder, provides a way to
encode objects (and scalar values) into an architecture-independent
format that can be stored in a file. When you archive a set of
objects, the class information and instance variables for each object
are written to the archive. The companion class NSKeyedUnarchiver
decodes the data in an archive and creates a set of objects equivalent to the original set.
-In the simplest way- as follows:
let array = [[1,2,"preved"], [3,4,"hola"], [5,6,"poka"]]
let encodedData = NSKeyedArchiver.archivedData(withRootObject: array)
if let decodedArray = NSKeyedUnarchiver.unarchiveObject(with: encodedData) as? [Any] {
// ...
}
Note that since array data type is [Array<Any>], you should cast it as [Any]
I'm having an issue getting a JSON array using Swift.
func getBenefitJSON() -> [AnyObject] {
let urlString = String("https://www.kyfb.com/KYFB/includes/themes/CodeBlue/display_objects/custom/remote/webservices/services.cfc?method=getMemberBenefits")
let url = URL(string: urlString!)
var data = Data()
do {
data = try Data(contentsOf: url!)
} catch {
}
print("URL Data: \(data)")
do {
let json = try JSONSerialization.jsonObject(with: data, options: JSONSerialization.ReadingOptions()) as! [AnyObject]
print("JSON: \(json)")
return json
} catch {
print("Could not get JSON")
return []
}
}
I get the data from the url but get an empty array returned. What am I doing wrong?
URL Data: 42769 bytes
Could not get JSON
Below is the response of JSON
[{"image":"https://cdn.kyfb.com/KYFB/cache/file/70162997-E06B-E9B6-88514280CA8397CC_medium.jpg","description":"","link":"https://www.kyfb.com/insurance/insurance-products/","name":"KFB Insurance","children":[]}, ...]
Below is the error
UserInfo={NSDebugDescription=JSON text did not start with array or object and option to allow fragments not set.}
I've also validated the response from the URL at jsonlint.com
URL data as string:
<wddxPacket version='1.0'><header/><data><string>[{"image":"https://cdn.kyfb.com/KYFB/cache/file/70162997-E06B-E9B6-88514280CA8397CC_medium.jpg","description":"","link":"https://www.kyfb.com/insurance/insurance-products/","name":"KFB Insurance","children":[]}, ...]</string></data></wddxPacket>)
I tested your code and it is working if the top level of the JSON is an Array. So the JSON you want to read is probably not an array but a dictionary.
To read the Dictionary you need to change the return type from [AnyObject] into [String:AnyObject] and all other occurrences of this type.
Nevertheless, I would recommend to use SwiftyJSON for working with JSON in Swift.