Use an NSNumberFormatter
:
NSNumberFormatter *f = [[NSNumberFormatter alloc] init];
f.numberStyle = NSNumberFormatterDecimalStyle;
NSNumber *myNumber = [f numberFromString:@"42"];
If the string is not a valid number, then myNumber
will be nil
. If it is a valid number, then you now have all of the NSNumber
goodness to figure out what kind of number it actually is.