Regex issue in IOS Program - ios

Question

I am trying to get the following regex to work on ios in order to make sure the user is only inputting numbers and a dot. I am not able to get number of matches to be above 0. I have also tried NSRange one as well and that will give me 0 no matter what as well, so my regex is not working, even thought I am pretty sure it should with what I have there. Any suggestions.
The Code I wrote is here with errorRegex is defined in the .h file and regError is defined as well.
errorRegex = [NSRegularExpression regularExpressionWithPattern:#"[^0-9.]*"
options: NSRegularExpressionCaseInsensitive error:&regError];
NSUInteger rangeOfFirstMatch = [errorRegex numberOfMatchesInString:servAmount1TF.text
options:0 range:NSMakeRange(0, [servAmount1TF.text length])];

Answer 1

Why not use stock-standard c's regex.h ?
See an example here:
http://cboard.cprogramming.com/c-programming/117525-regex-h-extracting-matches.html
And more information here:
https://stackoverflow.com/a/422159/1208218

Answer 2

errorRegex is of type NSRegularExpression, but the error is of type UIButtonContent. This has all the halmarks of a memory error. Something in your code not going though a proper retain/release cycle.
I got a unit test to work with the expression #"[^0-9.]+"
- (void)testRE
{
NSError *regError = nil;
NSRegularExpression *errorRegex;
NSString *string;
NSUInteger count;
errorRegex = [NSRegularExpression regularExpressionWithPattern:#"[^0-9.]+"
options: NSRegularExpressionCaseInsensitive
error:&regError];
STAssertNil(regError, nil);
string = #"00.0";
count = [errorRegex numberOfMatchesInString:string
options:0
range:NSMakeRange(0, [string length])];
STAssertEquals(count, 0U, nil);
string = #"00A00";
count = [errorRegex numberOfMatchesInString:string
options:0
range:NSMakeRange(0, [string length])];
STAssertEquals(count, 1U, nil);
}

Answer 3

NSRegularExpression *errorCheckRegEx = [[NSRegularExpression alloc] initWithPattern:#"\\b^([0-9]+(\\.)?[0-9]*)$|^([0-9]*(\\.)?[0-9]+)$|^[0-9]*$|^([0-9]*(\\/)?[0-9]*)$\\b" options:NSRegularExpressionCaseInsensitive error:nil];
[match setArray: [errorCheckRegEx matchesInString:servAmount1TF.text options:0 range:NSMakeRange(0, [servAmount1TF.text length])]];
I figured out what I needed to do when I could finally get back to it so if anyone was interested this is what I came up with. The \b is just what ios uses in their regexp which is kind of dumb, but it will not work without that so I leave it there when it doesn't feel natural to do especially after ruby's example. This regular expression will get fractions, decimals -> .3; 2.3; 2; and does it from the front to end of the line. What I think might have been happening was the fact that I was not using the \b and also not matching correctly, which is the second line. Either way it works great now. Thanks for the help.