Question

I’m writing a Cocoa application, which uses NSURLs — I need to remove the fragment portion of the URL (the #BLAH part).

example: http://example.com/#blah should end up as http://example.com/

I found some code in WebCore that seems to do it by using CFURL functionality, but it never finds the fragment portion in the URL. I’ve encapsulated it in a extension category:

-(NSURL *)urlByRemovingComponent:(CFURLComponentType)component {
    CFRange fragRg = CFURLGetByteRangeForComponent((CFURLRef)self, component, NULL);
    // Check to see if a fragment exists before decomposing the URL.
    if (fragRg.location == kCFNotFound)
        return self;

    UInt8 *urlBytes, buffer[2048];
    CFIndex numBytes = CFURLGetBytes((CFURLRef)self, buffer, 2048);
    if (numBytes == -1) {
        numBytes = CFURLGetBytes((CFURLRef)self, NULL, 0);
        urlBytes = (UInt8 *)(malloc(numBytes));
        CFURLGetBytes((CFURLRef)self, urlBytes, numBytes);
    } else
        urlBytes = buffer;

    NSURL *result = (NSURL *)CFMakeCollectable(CFURLCreateWithBytes(NULL, urlBytes, fragRg.location - 1, kCFStringEncodingUTF8, NULL));
    if (!result)
        result = (NSURL *)CFMakeCollectable(CFURLCreateWithBytes(NULL, urlBytes, fragRg.location - 1, kCFStringEncodingISOLatin1, NULL));

    if (urlBytes != buffer) free(urlBytes);
    return result ? [result autorelease] : self;
}
-(NSURL *)urlByRemovingFragment {
    return [self urlByRemovingComponent:kCFURLComponentFragment];
}

This is used as such:

NSURL *newUrl = [[NSURL URLWithString:@"http://example.com/#blah"] urlByRemovingFragment];

unfortunately, newUrl ends up being “http://example.com/#blah” because the first line in urlByRemovingComponent always returns kCFNotFound

I’m stumped. Is there a better way of going about this?

Working Code, thanks to nall

-(NSURL *)urlByRemovingFragment {
    NSString *urlString = [self absoluteString];
    // Find that last component in the string from the end to make sure to get the last one
    NSRange fragmentRange = [urlString rangeOfString:@"#" options:NSBackwardsSearch];
    if (fragmentRange.location != NSNotFound) {
        // Chop the fragment.
        NSString* newURLString = [urlString substringToIndex:fragmentRange.location];
        return [NSURL URLWithString:newURLString];
    } else {
        return self;
    }
}

Answer 1

How about this:

NSString* s = @"http://www.somewhere.org/foo/bar.html/#label";
NSURL* u = [NSURL URLWithString:s];

// Get the last path component from the URL. This doesn't include
// any fragment.
NSString* lastComponent = [u lastPathComponent];

// Find that last component in the string from the end to make sure
// to get the last one
NSRange fragmentRange = [s rangeOfString:lastComponent
                                 options:NSBackwardsSearch];

// Chop the fragment.
NSString* newURLString = [s substringToIndex:fragmentRange.location + fragmentRange.length];

NSLog(@"%@", s);
NSLog(@"%@", newURLString);