同一labeltext设置不同的属性

        NSMutableAttributedString *attributeString =  [[NSMutableAttributedString alloc] initWithString:title];                [attributeString addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:15] range:NSMakeRange(0, 4)];        [attributeString addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:13] range:NSMakeRange(4,[title length]- 4)];        [attributeString addAttribute:NSForegroundColorAttributeName value:[UIColor orangeColor] range:NSMakeRange(4,[title length]- 4)];        _naviLabel.attributedText = attributeString;