save value in userdefaults swift 4 code example

Example: save date to userdefaults swift

//save as Date
UserDefaults.standard.set(Date(), forKey: key)

//read
let date = UserDefaults.standard.object(forKey: key) as! Date
let df = DateFormatter()
df.dateFormat = "dd/MM/yyyy HH:mm"
print(df.string(from: date))