-(void)setHTMLTextToLab:(UILabel *)lab withHTMLStr:(NSString *)htmlStr
{
//str是要显示的字符串
NSMutableAttributedString * attrString = [[NSMutableAttributedString alloc] initWithData:[htmlStr dataUsingEncoding:NSUnicodeStringEncoding] options:@{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType} documentAttributes:nil error:nil];
[attrString addAttributes:@{NSBaselineOffsetAttributeName: @(5),//设置基线偏移值,取值为 NSNumber (float),正值上偏,负值下偏,可使UILabel文本垂直居中
NSFontAttributeName:[UIFont systemFontOfSize:14]} range:NSMakeRange(0, attrString.length)];
lab.attributedText = attrString;
//计算html字符串高度
NSMutableAttributedString *htmlString =[[NSMutableAttributedString alloc] initWithData:[htmlStr dataUsingEncoding:NSUTF8StringEncoding] options:@{NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType, NSCharacterEncodingDocumentAttribute:[NSNumber numberWithInt:NSUTF8StringEncoding]} documentAttributes:NULL error:nil];
[htmlString addAttributes:@{NSFontAttributeName:[UIFont systemFontOfSize:14]} range:NSMakeRange(0, htmlString.length)];
//
CGSize textSize = [htmlString boundingRectWithSize:(CGSize){kScreenH - 20, CGFLOAT_MAX} options:NSStringDrawingUsesLineFragmentOrigin context:nil].size;
//
lab.textAlignment = NSTextAlignmentCenter;
lab.numberOfLines = 0 ;
lab.frame = CGRectMake(0, lab.frame.origin.y, [UIScreen mainScreen].bounds.size.width, textSize.height);
}