NSRegularExpression for retrieving numbers from a string

I had used NSScanner for retrieving numbers from below text. But sometimes the result is not like what is expected. Heard that NSRegularExpres开发者_如何学Gosion class which is available fro iOS 4 is better to do this type of extraction. As I am a beginner on NSRegularExpression, I found the documentation provided by Apple is difficult to understand. Any help will be greatly appreciated. Thanks.

Input:

1D03 04 10 17 47 D24--

Output:

03 04 10 17 47 24

The first 5 sets of numbers should be less than 59 and last set should be less than 39.

try this ..

NSString *originalString = @"1D03 04 10 17 47 D24---";

NSLog(@"%@", originalString);
NSMutableString *strippedString = [NSMutableString 
                                   stringWithCapacity:originalString.length];

NSScanner *scanner = [NSScanner scannerWithString:originalString];
NSCharacterSet *numbers = [NSCharacterSet 
                           characterSetWithCharactersInString:@"0123456789  "];

while ([scanner isAtEnd] == NO) {
    NSString *buffer;
    if ([scanner scanCharactersFromSet:numbers intoString:&buffer]) {
        [strippedString appendString:buffer];

    } else {
        [scanner setScanLocation:([scanner scanLocation] + 1)];
    }
}

NSLog(@"%@", strippedString);

Or this:

NSString *string = @"1D03 04 10 17 47 D24---";

NSError *error = NULL;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"\\S*(\\d{2})\\S*"
                                                                       options:NSRegularExpressionCaseInsensitive
                                                                         error:&error];


NSString *modifiedString = [regex stringByReplacingMatchesInString:string
                                                           options:0
                                                             range:NSMakeRange(0, [string length])
                                                      withTemplate:@"$1"];

This Regular Expression matches everything which starts and ends with 0 or more non withspace Charcters (\S) and has in the middle two digits (\d). The matches are replaced by the tow digits in the middle of the string.