How to convert a JSON string to a dictionary?
Warning: this is a convenience method to convert a JSON string to a dictionary if, for some reason, you have to work from a JSON string. But if you have the JSON data available, you should instead work with the data, without using a string at all.
Swift 3
func convertToDictionary(text: String) -> [String: Any]? { if let data = text.data(using: .utf8) { do { return try JSONSerialization.jsonObject(with: data, options: []) as? [String: Any] } catch { print(error.localizedDescription) } } return nil}let str = "{\"name\":\"James\"}"let dict = convertToDictionary(text: str)Swift 2
func convertStringToDictionary(text: String) -> [String:AnyObject]? { if let data = text.dataUsingEncoding(NSUTF8StringEncoding) { do { return try NSJSONSerialization.JSONObjectWithData(data, options: []) as? [String:AnyObject] } catch let error as NSError { print(error) } } return nil}let str = "{\"name\":\"James\"}"let result = convertStringToDictionary(str)Original Swift 1 answer:
func convertStringToDictionary(text: String) -> [String:String]? { if let data = text.dataUsingEncoding(NSUTF8StringEncoding) { var error: NSError? let json = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.allZeros, error: &error) as? [String:String] if error != nil { println(error) } return json } return nil}let str = "{\"name\":\"James\"}"let result = convertStringToDictionary(str) // ["name": "James"]if let name = result?["name"] { // The `?` is here because our `convertStringToDictionary` function returns an Optional println(name) // "James"}In your version, you didn't pass the proper parameters to NSJSONSerialization and forgot to cast the result. Also, it's better to check for the possible error. Last note: this works only if your value is a String. If it could be another type, it would be better to declare the dictionary conversion like this:
let json = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.allZeros, error: &error) as? [String:AnyObject]and of course you would also need to change the return type of the function:
func convertStringToDictionary(text: String) -> [String:AnyObject]? { ... }
I've updated Eric D's answer for Swift 5:
func convertStringToDictionary(text: String) -> [String:AnyObject]? { if let data = text.data(using: .utf8) { do { let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String:AnyObject] return json } catch { print("Something went wrong") } } return nil}
Swift 3:
if let data = text.data(using: String.Encoding.utf8) { do { let json = try JSONSerialization.jsonObject(with: data, options: .mutableContainers) as? [String:Any] print(json) } catch { print("Something went wrong") }}