iOS 计算label的高度

+ (CGFloat)labelHeight:(UILabel *)label lines:(NSInteger)lines

{

    NSRange range = NSMakeRange(0, label.attributedText.length);

    NSDictionary *dic = [label.attributedText attributesAtIndex:0 effectiveRange:&range];

    CGSize size = CGSizeMake(label.bounds.size.width, 10000);

    

    CGFloat height = [label.text boundingRectWithSize:size options:NSStringDrawingUsesLineFragmentOrigin | NSStringDrawingUsesFontLeading attributes:dic context:nil].size.height;

    

    return height + 10.0f * lines;

}