Question

我目前正在使用此answer提供的此扩展程序将html转换为UITextView内的字符串。一切都很完美，但由于某些奇怪的原因，NSFontAttributeName在此过程中未应用于字符串。我在这里做错了吗？（或者我应该在使用归属的html解析字符串后应用NSAttributedString吗？如果是，是否可以将属性应用于NSAttributeString？）。

PS。使用html2String时字体大小不会更改，但html中的链接会被UITextView

更长时间识别

extension String {

    var html2AttributedString: NSAttributedString? {
        guard
            let data = dataUsingEncoding(NSUTF8StringEncoding)
            else { return nil }
        do {
            return try NSAttributedString(data: data, options: [NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType,NSCharacterEncodingDocumentAttribute:NSUTF8StringEncoding, NSFontAttributeName : UIFont.systemFontOfSize(17.0)], documentAttributes: nil)
        } catch let error as NSError {
            print(error.localizedDescription)
            return  nil
        }
    }
    var html2String: String {
        return html2AttributedString?.string ?? ""
    }
}
cell.desc.attributedText  = apiData[currentIndex].description!.html2AttributedString //Font attribute not recognized
cell.desc.text  = apiData[currentIndex].description!.html2String //Font recognized by links no longer recognized

Answer 1

我不确定为什么（可能是因为有一个范围）但是如果您首先创建一个NSMutableAttributedString然后添加UIFont属性，它就会起作用：

extension String {

    var html2AttributedString: NSMutableAttributedString? {
        guard
            let data = dataUsingEncoding(NSUTF8StringEncoding)
            else { return nil }
        do {
            let attrStr = try NSMutableAttributedString(data: data, options: [NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType,NSCharacterEncodingDocumentAttribute:NSUTF8StringEncoding], documentAttributes: nil)
            attrStr.addAttributes([NSFontAttributeName: UIFont.systemFontOfSize(17.0)], range: NSRange(location: 0, length: attrStr.length))
            return attrStr
        } catch let error as NSError {
            print(error.localizedDescription)
            return  nil
        }
    }
    var html2String: String {
        return html2AttributedString?.string ?? ""
    }
}

Answer 2

此处我已更新为 SWIFT 3

extension String {

    var utf8Data: Data? {
        return data(using: .utf8)
    }
}

extension Data {
    var attributedString: NSAttributedString? {
        do {
            return try NSAttributedString(data: self, options:[NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType, NSCharacterEncodingDocumentAttribute: String.Encoding.utf8.rawValue,NSForegroundColorAttributeName:UIColor.white,NSFontAttributeName:UIFont.systemFont(ofSize: 15)], documentAttributes: nil)
        } catch let error as NSError {
            print(error.localizedDescription)
        }
        return nil
    }

    var attributedStringHtml: NSMutableAttributedString? {
        do {
         let   attrStr = try NSMutableAttributedString(data: self, options: [NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType,NSCharacterEncodingDocumentAttribute:String.Encoding.utf8.rawValue], documentAttributes: nil)
            attrStr.addAttributes([NSFontAttributeName: UIFont.systemFont(ofSize: 17.0),NSForegroundColorAttributeName:UIColor.white], range: NSRange(location: 0, length: attrStr.length))
            return attrStr
        } catch let error as NSError {
            print(error.localizedDescription)
        }
        return nil
    }
}

<强>用法

 DispatchQueue.global(qos: .background).async {
            let attribut = self.sampleText.utf8Data?.attributedStringHtml
            DispatchQueue.main.async {
                self.convertedTextLbl.attributedText = attribut
            }
        }

NSFontAttributeName未应用于NSAttributedString

2 个答案: