Converting HTML Tag to String

Question

I want to convert HTML Tag to String, I used enum to find the content length of the String, according to the length i need to do some operations.

My modal class,

class PostViewModel {
    var content: TextContent
    enum TextContent {
            case expanded(String)
            case collapsed(String)

            static func == (lhs: TextContent, rhs: TextContent) -> Bool {
                switch lhs {
                case .collapsed(let content):
                    if case collapsed(content) = rhs {
                        return true
                    }
                    return false
                case .expanded(let content):
                    if case expanded(content) = rhs {
                        return true
                    }
                    return false
                }
            }
        }
    }

And i am calling this function in cellForItem(at index: Int),

func applyVerticalSizeConcernedRendering(fromViewModel viewModel: PostViewModel) {
    switch viewModel.content {
        case .collapsed(let content):
            let str = content.html2String
            print(str)
        case .expanded(let content):
            break
    }
}

html2String is extension class of String

extension String {
      var html2AttributedString: NSMutableAttributedString? {
      guard let data = data(using: String.Encoding.utf8) else { return nil }
            let attrs: [String: Any] = [
                NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType,
                NSCharacterEncodingDocumentAttribute: String.Encoding.utf8.rawValue
            ]
            do {
                let attrStr = try NSMutableAttributedString(data: data, options: attrs, documentAttributes: nil)
                return attrStr
            } catch let error as NSError {
                print(error.localizedDescription)
                return  nil
            }
        }
        var html2String: String {
            return html2AttributedString?.string ?? ""
        }
    }

The problem is it's crashing while converting HTML tag to String

It's crashing here,

let attrStr = try NSMutableAttributedString(data: data, options: attrs, documentAttributes: nil)

And the String is not empty

Below is the example HTML String,

<strong>I want to test HTML Tags<br><\/strong>dsfhjdjf sjdfdj  djfjdfj djkf dfjdhf <strong>adjf<br>asks <\/strong>djfdkf<br><strong>dfdjk dkfjdk <\/strong>dfjik iai <strong>adsfhj<\/strong>

This is working fine when i tried with hardcode value, but it's crashing only when i get the String from the enum

The crash log is,

*** Terminating app due to uncaught exception 'NSRangeException', reason: '*** -[__NSArrayM objectAtIndex:]: index 0 beyond bounds for empty array'

Can anyone please help in this?

Answer 1

Try out this instead, no need to do the whole process that you have done:

extension String {
    var htmlAttributedString: NSAttributedString? {
        do {
            return try NSAttributedString(data: Data(utf8), options: [NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType, NSCharacterEncodingDocumentAttribute: String.Encoding.utf8.rawValue], documentAttributes: nil)
        } catch {
            print("error:", error)
            return nil
        }
    }
    var htmlString: String {
        return htmlAttributedString?.string ?? ""

}

Usage:

let html = "<strong>I want to test HTML Tags<br></strong>dsfhjdjf sjdfdj  djfjdfj djkf dfjdhf <strong>adjf<br>asks</strong>djfdkf<br><strong>dfdjk dkfjdk </strong>dfjik iai <strong>adsfhj</strong>"
let str = html.htmlString

So you basically just use the String extension on your Strings. This is what I use in my projects

Update:
The above prints the following:

Here is a example project that you can try.