Save Global variable or a php like session - xcode

Question

I'm working on my app but i need some help.
I need a 'php-like session' in Objective C (without using connection to the internet)
I've thought about global vars, but my app seems to reset them when reloading the view.
This is my current code
SecondViewController.h
#interface SecondViewController : UIViewController
{
NSString * string;
}
SecondViewController.m
#interface SecondViewController ()
#end
#implementation SecondViewController
- (void)viewDidLoad
{
[super viewDidLoad];
if (! [string isEqualToString:#"Hello"])
{
NSLog(#"Hello");
string = #"Hello";
}
else
{
NSLog(#"Bye");
}
}
#end
But everytime I reload SecondViewController the 'string' is reseted to its default value.
I'm looking for something that we use in php (a.e. $_SESSION['string'] = 'hello')

Answer 1

It could be helpful to you . It stores the values until unless delete the app from your device .
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
// saving an NSString
[prefs setObject:#"TextToSave" forKey:#"keyToLookupString"];
// saving an NSInteger
[prefs setInteger:42 forKey:#"integerKey"];
// saving a Double
[prefs setDouble:3.1415 forKey:#"doubleKey"];
// saving a Float
[prefs setFloat:1.2345678 forKey:#"floatKey"];
// This is suggested to synch prefs, but is not needed (I didn't put it in my tut)
[prefs synchronize];
**Retrieving**
NSUserDefaults *prefs = [NSUserDefaults standardUserDefaults];
// getting an NSString
NSString *myString = [prefs stringForKey:#"keyToLookupString"];
// getting an NSInteger
NSInteger myInt = [prefs integerForKey:#"integerKey"];
// getting an Float
float myFloat = [prefs floatForKey:#"floatKey"];