How to check if NSUserDefaults exist

Question

I have been looking for an answer but not really found what i am looking for.

I have an application and is using NSUserDefaults to store 'currentGameStatus' and would like to ask the following questions:

How do i check if the NSUserDefaults .plist exists? Need this to determine if i need to create it for the first time and if so fill it with default values
Where do i find it on my Mac (running simulator)? Would need to delete it to test if the first run works?

In terms of your second question, see the existing [Easy way to see saved NSUserDefaults?](http://stackoverflow.com/questions/1676938/easy-way-to-see-saved-nsuserdefaults) question/answer. — John Parker, Jan 23 '11 at 15:57

score 22 · Answer 1 · answered Jan 23 '11 at 15:58

you don't check.

you register your defaults. and if you haven't saved a value the default will be used.

NSDictionary *defaultUserDefaults = [NSDictionary dictionaryWithObjectsAndKeys:
                                     [NSNumber numberWithBool:NO], @"Foo",
                                     @"Bar", @"Baz",
                                     [NSNumber numberWithInteger:12], @"FooBar",
                                     nil];
[[NSUserDefaults standardUserDefaults] registerDefaults:defaultUserDefaults];

and you do this every time your app launches.

Wow, I cannot believe I missed that. +1 to you. – Jacob Relkin Jan 23 '11 at 16:09 — Jacob Relkin, Jan 23 '11 at 16:09

score 10 · Accepted Answer · answered Jan 23 '11 at 15:56

10

The way I do it is I set a BOOL flag in NSUserDefaults if it doesn't already exist:

if(![[NSUserDefaults standardUserDefaults] boolForKey:@"firstRun"]) {
   //do initialization stuff here...

   [[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"firstRun"];
}

answered Jan 23 '11 at 15:56

Jacob Relkin

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what if later on, i set the first run to false? it will still get into the if statement and set back to YES – Kiddo Sep 25 '13 at 15:44

score 1 · Answer 3 · answered Jan 23 '11 at 15:55

1

NSUserDefaults already exists by default. You can add to it by [[NSUserDefaults standardUserDefaults] setObject:@"object" forKey:@"key"];
You can find the NSUserDefaults .plist here

answered Jan 23 '11 at 15:55

timothy5216

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How to check if NSUserDefaults exist

3 Answers3