XML解析器读取通道描述标签

Question

我有一个解析sharontalon.com/feed供稿的xml解析器 但是，当将字符串放入表格时，将使用Feed的描述作为第一个项目描述，将所有帖子描述碰到一个项目。如何跳过第一个描述标签？

http://i.stack.imgur.com/9kYVT.png

这是XMLParser

  import UIKit



@objc protocol XMLParserDelegate{

func parsingWasFinished()

}



class XMLParser: NSObject, NSXMLParserDelegate {

   

var arrParsedData = [Dictionary<String, String>]()



var currentDataDictionary = Dictionary<String, String>()



var currentElement = ""



var foundCharacters = ""



var delegate : XMLParserDelegate?





func startParsingWithContentsOfURL(rssURL: NSURL) {

    let parser = NSXMLParser(contentsOfURL: rssURL)

    parser!.delegate = self

    parser!.parse()

}











func parserDidEndDocument(parser: NSXMLParser) {

    delegate?.parsingWasFinished()

}





func parser(parser: NSXMLParser, didStartElement elementName: String!, namespaceURI: String!, qualifiedName qName: String!, attributes attributeDict: [String : String]) {

    

    currentElement = elementName

}





func parser(parser: NSXMLParser, didEndElement elementName: String!, namespaceURI: String!, qualifiedName qName: String!) {

    if !foundCharacters.isEmpty {

        

        if elementName == "link" || elementName == "description"{

            foundCharacters = (foundCharacters as NSString).substringFromIndex(3)

        }

        

        

        currentDataDictionary[currentElement] = foundCharacters

        

        foundCharacters = ""

        

        if currentElement == "pubDate" {

            arrParsedData.append(currentDataDictionary)

        }

        

    }

}





func parser(parser: NSXMLParser, foundCharacters string: String!) {

    if (currentElement == "title" ) || currentElement == "description" || currentElement == "link" || currentElement == "pubDate"{

        foundCharacters += string

    }

}





func parser(parser: NSXMLParser, parseErrorOccurred parseError: NSError!) {

    print(parseError.description)

}





func parser(parser: NSXMLParser, validationErrorOccurred validationError: NSError!) {

    print(validationError.description)

}



}

这是TableView控制器

import UIKit



class TopicsTableViewController: UITableViewController, XMLParserDelegate {



    var xmlParser : XMLParser!

    

    override func viewDidLoad() {

        super.viewDidLoad()

        

        let url = NSURL(string: "http://sharontalon.com/feed")

        xmlParser = XMLParser()

        xmlParser.delegate = self

        xmlParser.startParsingWithContentsOfURL(url!)

    }



    override func didReceiveMemoryWarning() {

        super.didReceiveMemoryWarning()

        // Dispose of any resources that can be recreated.

    }



    

    // MARK: XMLParserDelegate method implementation

    

    func parsingWasFinished() {

        self.tableView.reloadData()

    }

    

    

  



    override func numberOfSectionsInTableView(tableView: UITableView) -> Int {

        return 1

    }



    override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {

        return xmlParser.arrParsedData.count

    }



    

    override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

        let cell = tableView.dequeueReusableCellWithIdentifier("idCell", forIndexPath: indexPath) 

        

        let currentDictionary = xmlParser.arrParsedData[indexPath.row] as Dictionary<String, String>

        

        cell.textLabel?.text = currentDictionary["title"]

        cell.detailTextLabel?.text = currentDictionary["description"]

        return cell

    }

    

    

    override func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {

        return 80

    }

    

    

    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {

        let dictionary = xmlParser.arrParsedData[indexPath.row] as Dictionary<String, String>

        let tutorialLink = dictionary["link"]

        let publishDate = dictionary["pubDate"]

        

        let tutorialViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewControllerWithIdentifier("idTutorialViewController") as! TutorialViewController

        

        tutorialViewController.tutorialURL = NSURL(string: tutorialLink!)

        tutorialViewController.publishDate = publishDate

        

        showDetailViewController(tutorialViewController, sender: self)

        

    }

    


}

感谢您的帮助

Answer 1

问题正在发生，因为在您的XML数据中，description标记内有一个cannel标记，当您到达arrParsedData时，您正在将数据插入pubDate字典} 来自之前下一个description代码，你运气不好，因为channel代码已包含description代码，所以你感觉不舒服错误。但如果它没有，则会发生异常，告诉您没有名为description的标签。我改变了你的状况

 if currentElement == "pubDate"

到：

if currentElement == "description" && !isFirst

我添加了isFirst变量，以避免description标记下的第一个channel标记。请注意我已添加的else部分

if currentElement == "description" && !isFirst

        {
            arrParsedData.append(currentDataDictionary)   
        }else {
            if currentElement == "description" && isFirst {
                isFirst = false
            }
        }

这是结果的屏幕截图：

这是新的XMLParserDelegate。我还纠正了NSXMLParserDelegate方法的一些签名

 import UIKit

 @objc protocol XMLParserDelegate{

    func parsingWasFinished()

 }

 class XMLParser: NSObject, NSXMLParserDelegate {
    var arrParsedData = [Dictionary<String, String>]()
    var currentDataDictionary = Dictionary<String, String>()
    var currentElement = ""
    var foundCharacters = ""
    var delegate : XMLParserDelegate?
    var isFirst = true
    func startParsingWithContentsOfURL(rssURL: NSURL) {

        let parser = NSXMLParser(contentsOfURL: rssURL)

        parser!.delegate = self

        parser!.parse()

    }


    func parserDidEndDocument(parser: NSXMLParser) {

        delegate?.parsingWasFinished()

    }

    func parser(parser: NSXMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String]) {
        currentElement = elementName
    }

    func parser(parser: NSXMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {


            if !foundCharacters.isEmpty {
                if elementName == "link" || elementName == "description" {
                    foundCharacters = (foundCharacters as NSString).substringFromIndex(3)
                }
                currentDataDictionary[currentElement] = foundCharacters

                foundCharacters = ""

                if currentElement == "description" && !isFirst

                {
                    arrParsedData.append(currentDataDictionary)
                }else {
                    if currentElement == "description" && isFirst {
                        isFirst = false
                    }
                }
            }

    }

    func parser(parser: NSXMLParser, foundCharacters string: String) {

        if currentElement == "title"  || currentElement == "description"
            || currentElement == "link" || currentElement == "pubDate"
        {

            foundCharacters += string

        }

    }

    func parser(parser: NSXMLParser, parseErrorOccurred parseError: NSError) {

        print(parseError.description)

    }

    func parser(parser: NSXMLParser, validationErrorOccurred validationError: NSError) {

        print(validationError.description)

    }

 }