设置行间距

NSMutableParagraphStyle *paragraphStyle =[[NSMutableParagraphStyle alloc]init];    paragraphStyle.lineSpacing=50;        

NSDictionary*attributes = @{ NSFontAttributeName:[UIFont systemFontOfSize:14], NSParagraphStyleAttributeName:paragraphStyle};    

label.attributedText=[[NSAttributedString alloc]initWithString:label.text attributes:attributes];}