How to get the first image URL from NSString ?

I am working on a RSS feed reader and I need to get the first image URL from the feed post. A simple function to get the first image URL from the HTML contents.

- (NSString *)getFirstImageUrl: (NSString *) html {
    NSString *tempText = [[NSString alloc]initWithFormat:@""];
    NSScanner * pageScanner = [NSScanner scannerWithString:html];
    [pageScanner setCaseSensitive:NO];
    [pageScanner setCharactersToBeSkipped:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
    [pageScanner scanUpToString:@"<img " intoString:nil];
    [pageScanner scanString:@"<img " intoString:nil];
    [pageScanner scanUpToString:@"src="" intoString:nil];
    [pageScanner scanString:@"src="" intoString:nil];
    [pageScanner scanUpToString:@""" intoString:&tempText];
    return tempText;
}

You can even get all the images in an NSMutable Array using a loop.

Update : July 11, 2011, 7:22 am

I have not used [tempText Release] or any other release as this code is with iOS 5 where you do not need to manage memory manually.