解析iPhone应用程序的RSS/Atom提要的最佳方法是什么？

import Foundation

class RSSParser: NSObject, XMLParserDelegate {
    var parser: XMLParser?
    var items: [RSSItem] = []
    var currentItem: RSSItem?
    var currentElement: String?

    func parse(rssFeedURL: URL) {
        parser = XMLParser(contentsOf: rssFeedURL)
        parser?.delegate = self
        parser?.parse()
    }

    func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String] = [:]) {
        currentElement = elementName
        if elementName == "item" {
            currentItem = RSSItem()
        }
    }

    func parser(_ parser: XMLParser, foundCharacters string: String) {
        if let currentItem = currentItem, let currentElement = currentElement {
            switch currentElement {
            case "title":
                currentItem.title += string
            case "link":
                currentItem.link += string
            case "pubDate":
                currentItem.pubDate += string
            case "description":
                currentItem.description += string
            default:
                break
            }
        }
    }

    func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
        if elementName == "item" {
            items.append(currentItem!)
            currentItem = nil
        }
        currentElement = nil
    }
}

let parser = RSSParser()
parser.parse(rssFeedURL: URL(string: "https://example.com/rss")!)