Swift 5.0 UILabel显示html标签的高度计算

let attrStr = try! NSMutableAttributedString(
            data: (answer.content.data(using: .unicode, allowLossyConversion: true)!),
            options:[.documentType: NSAttributedString.DocumentType.html,
                     .characterEncoding: String.Encoding.utf8.rawValue],
            documentAttributes: nil)
 //行高
let paraph = NSMutableParagraphStyle()
paraph.lineSpacing = 8
attrStr.addAttributes([NSAttributedStringKey.paragraphStyle:paraph],
                              range: NSMakeRange(0, attrStr.length))
        
self.answerLabel.attributedText = attrStr
//计算高度
let contentHegiht = attrStr.boundingRect(with: CGSize(width:  kScreenWitdh - 30, height: CGFloat(MAXFLOAT)), options: [.usesLineFragmentOrigin,.usesFontLeading], context: nil).height