let responseString = String(data: data, encoding: .utf8)
if responseString["is_valid"] == true {
print("Login Successful")
} else {
print("Login attempt failed")
}
I'm trying to get the value of "is_valid"
from responseString
dictionary. However, I have no idea how. Everything I've tried has failed.
responseString
looks like this when outputted via print()
:
{
"is_valid": true
}
You can use like this :
if let responseString = try? JSONSerialization.jsonObject(with: data, options: []) as? [String: Bool] {
if responseString!["is_valid"] == true {
print("Login Successful")
} else {
print("Login attempt failed")
}
}
For completeness, a solution using Swift 4 new encoding/decoding framework ;)
let response = try? JSONDecoder().decode([String: Bool].self, from: data)
if response?["is_value"] {
print("Login Successful")
} else {
print("Login attempt failed")
}
Parse the JSON in the data
with JSONSerialization
:
guard let json = try? JSONSerialization.jsonObject(with: data) as? [String: Any],
let isValue = json?["is_value"] as? Bool else {
// handle the failure to find `is_value` however you'd like here
return
}
if isValue { ... }
This is another way you could find the Boolean value and keep it stored in a Struct
{
"is_valid" = true
}
struct Session: Codable {
var isValid: Bool
//Create a coding key so you can match the struct variable name to JSON data key
private enum CodingKeys: String, CodingKey {
case isValid = "is_valid"
}
//Initialises and decodes the JSON data to fill your struct
init(from decoder: Decoder) throws {
let container = try decoder.container(keyedBy: CodingKeys.self)
self.isValid = try container.decode(Bool.self, forKey: .isValid)
}
}
Now let's say your loading from a JSON file within the app.
func loadJSONData(){
guard let url = Bundle.main.url(forResource: "myJSONFile", withExtension: "json") else { return }
do {
let data = try Data(contentsOf: url, options: .mappedIfSafe)
let decoder = JSONDecoder()
//decode data and populate Session struct
guard let jsonData = try? decoder.decode(Session.self, from: data) else {return}
if jsonData.isValid {
print("DO SOMETHING HERE)
}
}
}
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.