try this, but it's not for label but it's for textView.
NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:@"firstsecond"];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0,5)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(5,6)];
//[string addAttribute:NSUnderlineStyleAttributeName value:[NSNumber numberWithInt:10] range:NSMakeRange(0,5)];
[string addAttribute:NSLinkAttributeName value:[NSURL URLWithString:@"http://www.google.co.in"] range:NSMakeRange(0,5)];
[string addAttribute:NSLinkAttributeName value:[NSURL URLWithString:@"http://www.yahoo.com"] range:NSMakeRange(5,6)];
self.txtView.attributedText=string;
self.txtView.scrollEnabled = NO;
self.txtView.editable = NO;
self.txtView.textContainer.lineFragmentPadding = 0;
self.txtView.textContainerInset = UIEdgeInsetsMake(0, 0, 0, 0);
self.txtView.delegate = self;
}
- (BOOL)textView:(UITextView *)textView shouldInteractWithURL:(NSURL *)url inRange: (NSRange)characterRange
{
return YES;
}