Objective-C: Find numbers in string

Question

I have a string that contains words as well as a number. How can I extract that number from the string?

NSString *str = @\"This is my string. #1234\";
         


        

Answer 1

You could use the NSRegularExpression class, available since iOS SDK 4.

Bellow a simple code to extract integer numbers ("\d+" regex pattern) :

- (NSArray*) getIntNumbersFromString: (NSString*) string {

  NSMutableArray* numberArray = [NSMutableArray new];

  NSString* regexPattern = @"\\d+";
  NSRegularExpression* regex = [[NSRegularExpression alloc] initWithPattern:regexPattern options:0 error:nil];

  NSArray* matches = [regex matchesInString:string options:0 range:NSMakeRange(0, string.length)];
  for( NSTextCheckingResult* match in matches) {
      NSString* strNumber = [string substringWithRange:match.range];
      [numberArray addObject:[NSNumber numberWithInt:strNumber.intValue]];
  }

  return numberArray; 
}