All,
Yes, as a result of my impatience, I now have two possible solutions - well, it
beats having none.
....End of thread.
Joshua
josh_feinstein wrote:
> I've managed to solve the string manipulation kunumdrum that I had created.
> Instead of tangling myself up into a never ending "inconsistent data type"
> problem, I took a different approach.
> For anyone who may be interested, here it is...
>
> NSString * aString;
> NSCharacterSet * anInvertedCharSet;
> NSScanner * aStrTest;
>
> aString = [aString substringToIndex:3];
> aStrTest = [NSScanner scannerWithString:aString];
> ianInvertedCharSet = [[NSCharacterSet
> characterSetWithCharactersInString:@"0123456789"] invertedSet];
> if (![aStrTest scanUpToCharactersFromSet:(NSCharacterSet *)anInvertedCharSet
> intoString:NULL])
> {
> //rest of the code.....
> }
>
> josh_feinstein wrote:
>
> > Thank You for all of the helpful advice last friday. I think the is some
> > minor detail that I am overlooking. Anyway, here is the path I decided to
> > take...
> >
> > I only need the first 3 characters in the string, so I simply used the
> > "substringToIndex:" method. No problem.
> > I then used the NSCharacterSet class to call the method
> > "characterSetWithCharactersInString:invertedSet" and assigned the result to
> > an NSCharacterSet object.
> > Next, I used the method rangeOfCharacterFromSet and assigned the result to
> > an NSRange object...
> > Here is the code...
> >
> > NSString * aString;
> > NSCharacterSet * anInvertedCharSet;
> > NSRange * aRange;
> >
> > In appendToResponse:inContext
> >
> > aString = [aString substringToIndex:3]; //line114
> > anInvertedCharSet = [[NSCharacterSet
> > characterSetWithCharactersInString:@"0123456789"] invertedSet]; //line115
> > aRange = [aString rangeOfCharacterFromSet:anInvertedCharSet ]; //line116
> > if (aRange == nil) //line117
> >
> > The flow of my logic is sound (or sound enough). The problem is, I seem to
> > be violating some ObjC rule with respect to assigning data types.
> > Henceforth, here is what happened when I compiled...
> >
> > ThisFile.m: In function `-[ThisFile.m appendToResponse:inContext:]':
> > ThisFile.m:116: incompatible types in assignment
> > ThisFile.m:117: warning: comparison of distinct pointer types lacks a cast
> > ThisFile.m:77: warning: `aRange' might be used uninitialized in this
> > function
> >
> > Now, in the online documentation, it says that the NSString method
> > "rangeOfCharacterFromSet" takes as it's argument an NSCharacterSet object
> > (in this case "NSCharcterSet * anInvertedCharSet"0 and returns an NSRange
> > object (in this case "NSRange * aRange"), so according to the docs, I
> > shouldn't be getting this error. That is obviously not the case. There must
> > be some detail I am overlooking. Any suggestions would be very helpful.
> >
> > Thanks in advance,
> > Joshua
> >
> > josh_feinstein wrote:
> >
> > > I have an NSString object that I would like to test to make sure that it
> > > contains only numeric characters and no alpha characters. The test will
> > > happen almost everytime the user makes a request to the app, so I am
> > > trying to decide which is the tightest, quickest, most effiecient method
> > > to use. Should I convert the string into an NSNumber or NSArray or
> > > NSScanner class and what is the "best" method within one of these three
> > > classes to use?
> > >
> > > Thanks,
> > > Joshua
