Convert NSString to fetch synthesized information - iphone

Question

//COPY THIS CODE IN A FRESH PROJECT!!!
//THIS 2 LINES ARE JUST EXAMPLES, OF VALUES PUSHES OUT A DATABASE
NSString *messagelevel1 = #"45";
NSString *currentlevel = #"1";
NSString *HuidigLevel = currentlevel;
NSDecimalNumber *huidigleveldec = [[NSDecimalNumber alloc] initWithString: HuidigLevel];
float HuidigLevelRek = [huidigleveldec floatValue];
//HERE IS THE PROBLEM
NSString* LevelTotaal=[[NSString alloc] initWithFormat:#"messagelevel%.f",HuidigLevelRek];
NSString*result = LevelTotaal;
NSLog(#"%#",result);
// THE ABOVE RESULT SHOULD RETURN THE SAME VALUE AS THE NEXT (messagelevel1) LINE BUT IT RETURNS ONLY "messagelevel1" AND NOT THE VALUE!
NSLog(#"%#",messagelevel1);
I want the *result string behaves like the *huidiglevel string and fetch some information, but because the LevelTotaal is a NSString, It doesn't fetch this information. I really got no idea where to google for this problem, searching the Developer docs didn't helped either . Maybe you guys can help me out?
Actually the second NSLog returns the value and to first NSLog just returns messagelevel1. To tell you in short ;)
I hope you guys get what I'm saying!

Answer 1

I think what you're trying to do is use variable variables, a system that does not exist in Objective-C. In PHP, you can use variable variables:
$hello = 'abcdef';
$varName = 'hello';
print $$varName; // prints the value of $hello, which is 'abcdef'
Like many things in PHP, this is not really a good way to design software. Instead, consider using something like a NSDictionary, this allows you to give specific data a key.
NSMutableDictionary *aDict = [NSMutableDictionary dictionary];
[aDict setObject:[NSNumber numberWithFloat:4.5] forKey:#"messageLevel1"];
NSString *result = [aDict objectForKey:#"messageLevel1"];
You can obtain the data dynamically, the key can be generated or obtained at runtime.
Edit:
Rather than having variables called messageLevel1, messageLevel2, messageLevel3 ... messageLeveln, just use an array.
NSMutableArray *messageLevels = [NSMutableArray array];
[messageLevels addObject:#"1"];
[messageLevels addObject:#"45"];
[messageLevels addObject:#"123"];
NSString *result = [messageLevels objectAtIndex:HuidigLevelRek];