NSString IntValue exception when parsing notification userInfo

Question

I am implementing a login system that uses the NSNotifications userInfo dictionary to pass login info by notification. The dictionary gets passed ok but when I try to convert one of the NSStrings in the dictionary into an int using IntValue I get error. Even when I copy the dictionary object to another string I get the same error, but with a normal string there are no errors. Code:

- (void)loginComplete:(NSNotification *) notification {
    if ([[notification name] isEqualToString:@"Login Complete"]) {
        NSDictionary *loginInfo = [notification userInfo];

        loginString = [loginInfo objectForKey:@"login_string"];
        NSLog(@"%@", loginString);
        NSString* expString = [NSString stringWithString:[loginInfo objectForKey:@"expires_in"]];
        // [loginInfo objectForKey:@"expires_in"] == @"604700"
        expiresIn   = [expString intValue];
        NSLog(@"expiresIn: %i", expiresIn);

        NSString * toInt = @"112345";
        int realInt = [toInt intValue];
        NSLog(@"realInt: %i", realInt);
    }
}

So the first NSLog provides correct info, and the conversion in the end (test) also works, but the expiresIn results in an error:

2015-01-13 17:53:06.976 API_test_osx[2867:143430] -[__NSArrayM length]: unrecognized selector sent to instance 0x600000441d40
2015-01-13 17:53:06.976 API_test_osx[2867:143430] *** WebKit discarded an uncaught exception in the webView:didFinishLoadForFrame: delegate: <NSInvalidArgumentException> -[__NSArrayM length]: unrecognized selector sent to instance 0x600000441d40

If I try not to convert to int, the value can be logged just fine as a NSString. What am I doing wrong?

Can you show how you set a userInfo of NSNotification? Look this question maybe help: http://stackoverflow.com/questions/7896646/how-to-pass-object-with-nsnotificationcenter NSArray doens't have objectForKey! — weso, Jan 13 '15 at 16:16

score 2 · Accepted Answer · answered Jan 13 '15 at 16:06

2

The object you think is an NSString is in fact an NSArray as demonstrated by the error message:

-[__NSArrayM length]: unrecognized selector sent to instance 0x600000441d40

I cannot provide more information than that, other to say that if you are passing around integers within an Objective-C collection class then use an NSNumber object, not an NSString object.

answered Jan 13 '15 at 16:06

Droppy

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That makes sense, thank you. The third party code I used made the values into arrays of 1 length. What kept me from getting it was that I was still able to assign the values into NSString ivars, propably because it called implicitly the NSArrays toString method. I mark your answer as the right one. – MarekB Jan 13 '15 at 16:27
Also prefer using 'NSInteger' rather than 'int' and 'integerValue' rather than 'intValue' – KirkSpaziani Jan 13 '15 at 17:05

score 0 · Answer 2 · answered Jan 13 '15 at 16:16

0

It looks like your accessing an array of objects under the key you specify. You will also need to access the objects index value. Ie objectAtIndex. Hope this helps

answered Jan 13 '15 at 16:16

Tom

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Yeah, doing that now. Thanks. – MarekB Jan 13 '15 at 16:27

NSString IntValue exception when parsing notification userInfo

2 Answers2