ios - 如何在 swift 4 中将 html 字符串设置为标签时设置常规字体和粗体字体的自定义字体？

Question

我从 API 响应中获取 HTML 格式的字符串，因此我需要将其设置为标签，同时维护自定义字体(如我的应用程序)并应用样式(粗体、常规等)到标签。

我使用了一个扩展，可以将 HTML 字符串转换为带有换行符等的常规字符串。但是，我可以在此处设置字体，但只能设置一种字体，并且仅以常规字体显示，所以整个标签采用一种字体，我想要的是将粗体 HTML 部分设置为粗体，将常规字体设置为常规 HTML 部分/标签。

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
    }
}

//set converted html to string here
let whyAttendAttributedText: NSMutableAttributedString = NSMutableAttributedString(attributedString: attendData.whyAttendData?.desc?.htmlToAttributedString ?? NSAttributedString())

//set font here   
whyAttendAttributedText.addAttributes([NSMutableAttributedString.Key.font: CommonSettings.shared.getFont(type: .regular, size: descriptionLabel.font.pointSize), NSMutableAttributedString.Key.foregroundColor: UIColor.white], range: NSMakeRange(0, whyAttendAttributedText.length))

我想为文本设置粗体和常规字体，但由于我只设置了一种字体，所以无法获得结果，有没有办法像 HTML 中那样设置粗体和常规字体> 字符串？

Answer 1

这应该有帮助:

extension String {

func attributedString(withRegularFont regularFont: UIFont, andBoldFont boldFont: UIFont) -> NSMutableAttributedString {
    var attributedString = NSMutableAttributedString()
        guard let data = self.data(using: .utf8) else { return NSMutableAttributedString() }
        do {
            attributedString = try NSMutableAttributedString(data: data,
                                                             options: [.documentType: NSAttributedString.DocumentType.html,
                                                                       .characterEncoding:String.Encoding.utf8.rawValue],
                                                             documentAttributes: nil)
            let range = NSRange(location: 0, length: attributedString.length)
            attributedString.enumerateAttribute(NSAttributedString.Key.font, in: range, options: .longestEffectiveRangeNotRequired) { value, range, _ in
                let currentFont: UIFont         = value as! UIFont
                var replacementFont: UIFont?    = nil

                if currentFont.fontName.contains("bold") || currentFont.fontName.contains("Bold") {
                    replacementFont             =   boldFont
                } else {
                    replacementFont             =   regularFont
                }

                let replacementAttribute        =   [NSAttributedString.Key.font:replacementFont!]
                attributedString.addAttributes(replacementAttribute, range: range)
            }
        } catch let e {
            print(e.localizedDescription)
        }
       return attributedString
}
}