对于Swift 4：

extension String {
    var htmlToAttributedString: NSAttributedString? {
        guard let data = data(using: .utf8) else { return NSAttributedString() }
        do {
            return try NSAttributedString(data: data, options: [.documentType: NSAttributedString.DocumentType.html, .characterEncoding:String.Encoding.utf8.rawValue], documentAttributes: nil)
        } catch {
            return NSAttributedString()
        }
    }
    var htmlToString: String {
        return htmlToAttributedString?.string ?? ""
    }
}

然后，每当您要将HTML文本放入UITextView时，请使用：

textView.attributedText = htmlText.htmlToAttributedString