设置行间距

NSMutableParagraphStyle *muStyle = [[NSMutableParagraphStyle alloc]init];
muStyle.lineSpacing = 3;//设置行间距离
muStyle.alignment = NSTextAlignmentLeft;//对齐方式
NSMutableAttributedString *attrString = [[NSMutableAttributedString alloc] initWithString:model.mContent];
[attrString addAttribute:NSFontAttributeName value: H15 range:NSMakeRange(0, attrString.length)];
[attrString addAttribute:NSParagraphStyleAttributeName value:muStyle range:NSMakeRange(0, attrString.length)];
self.titleLabel.attributedText = attrString;