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iOS Objective-C Basics (Retired) Foundation Framework NSNumber

Rodrigo Chousal
Rodrigo Chousal
16,009 Points
Posted by Rodrigo Chousal
Rodrigo Chousal
16,009 Points

What's wrong here?

Instructions: Declare another variable named 'planck' of type NSNumber and assign it the value 6.626.

My Code:

NSNumber *foxtrot;
foxtrot = [ [NSNumber alloc] initWithInt: 24];
NSLog (@"foxtrot %@", foxtrot);
NSNumber *planck;
planck = [ [NSNumber alloc] initWithInt: 6.626];

3 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points 
initWithInt: 6.626]

6.626 is not an int, its a float

Rodrigo Chousal
Rodrigo Chousal
16,009 Points
Rodrigo Chousal
Rodrigo Chousal
16,009 Points

Oh, so should I write initWithFloat?

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

yeah try that. you could also use an NSNumber literal as well. 

NSNumber myNumber = @1.5;
Rodrigo Chousal
Rodrigo Chousal
16,009 Points
Rodrigo Chousal
Rodrigo Chousal
16,009 Points

What about this?

Instructions:

Declare a third NSString variable named 'favorite' and assign a concatenated string to it by appending the variable named 'color' to the variable named 'preference'. (Remember to use the method 'stringByAppendingString').

My Code:

NSString *color = @"Purple";
NSString *preference = @"My favorite color is ";
NSString *favorite = [[preference stringByAppendingString : color]];
Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

NSString *favorite = [[preference stringByAppendingString : color]];

you have too many brackets around the method call. Try

NSString *favorite = [preference stringByAppendingString:color];
Rodrigo Chousal
Rodrigo Chousal
16,009 Points
Rodrigo Chousal
Rodrigo Chousal
16,009 Points

You are the best. Thank you!