Question

I have some code in my classes to read from NSUserDefaults

NSUserDefaults *defs = [NSUserDefaults standardUserDefaults];
score = [defs integerForKey:@"score"];

this causes a crash.

Im guessing it is because the score value is nil or doesnt exist.

How can I check if it is nil?

EDIT.

The following code causes a crash when storing to NSUserDefaults.

NSUserDefaults *defs = [NSUserDefaults standardUserDefaults];
    [defs setInteger:0 forKey:@"score"];
    [defs setInteger:3 forKey:@"lives"];
    [defs release];

Im not sure what the issue is

On some crashes there isnt even a crash report in the console.

Thanks

Answer 1

As per the documentation, “if the specified key does not exist, this method returns 0”. So integerForKey will always return an NSInteger, even if you haven’t set it.

Edit:
Now you’ve edited your question, I can see the problem. You are releasing NSUserDefaults. There is no reason to do this. Remove the [release] line from your code.

[NSUserDefaults standardUserDefaults] returns a singleton class. You don’t own it, so you shouldn’t release it. Review the Apple Memory Mangement Rules if you’re confused about when to retain/release.