htmlアジリティパックで特定のノードを出力できません。＃

Question

私はC＃に精通するためにプロジェクトを構築しようとしています。特定のファイルがWebサイトに追加された日付を抽出したいと思っていました。私の例では、私はhttps://thepiratebay.org/search/rick%20and%20morty/0/99/0

を使用の事は、私が初めのために、このような何かをしようとするデータを抽出したいということです。

static void Main(string[] args) 
    { 
     string url = "https://thepiratebay.org/search/rick%20and%20morty/0/99/0"; 
     HtmlWeb web = new HtmlWeb(); 
     HtmlDocument doc = web.Load(url); 
     foreach (HtmlNode node in doc.DocumentNode.SelectNodes("//*[@id='searchResult']/tbody/tr[1]/td[2]/font")) 
     { 
      Console.WriteLine("you are looking for: " + node.InnerHtml.ToString()); 
     } 

     Console.ReadKey(); 
    } 
} 

プログラムとNullReferenceExceptionを実行した後にスローされます。 誰かが私を案内できますか？

Answer 1

NullReferenceExceptionがsearchResultの下にtbodyという要素がないためにスローされています。

我々は、HTMLのスニペットを見れば：

<table id="searchResult"> 
    <thead id="tableHead"> 
    ... 
    </thead> 
    <tr> 
     <td class="vertTh"> 
      <center> 
       <a href="/browse/200" title="More from this category">Video</a><br> 
       (<a href="/browse/208" title="More from this category">HD - TV shows</a>) 
      </center> 
     </td> 
     <td> 
      <div class="detName"> 
       <a href="/torrent/12678054/Rick_and_Morty_Season_2_[WEBRIP]_[1080p]_[HEVC]" class="detLink" title="Details for Rick and Morty Season 2 [WEBRIP] [1080p] [HEVC]"> 
        Rick and Morty Season 2 [WEBRIP] [1080p] [HEVC] 
       </a> 
      </div> 
      <a href="magnet:?xt=urn:btih:0494a80532b5b05dde567c61220d93406b7e22e7&dn=Rick+and+Morty+Season+2+%5BWEBRIP%5D+%5B1080p%5D+%5BHEVC%5D&tr=udp%3A%2F%2Ftracker.leechers-paradise.org%3A6969&tr=udp%3A%2F%2Fzer0day.ch%3A1337&tr=udp%3A%2F%2Ftracker.coppersurfer.tk%3A6969&tr=udp%3A%2F%2Fpublic.popcorn-tracker.org%3A6969" title="Download this torrent using magnet"> 
       <img src="//thepiratebay.org/static/img/icon-magnet.gif" alt="Magnet link"> 
      </a> 
      <a href="//cdn.bitx.tv/bx.php?torrent=bWFnbmV0Oj94dD11cm46YnRpaDowNDk0YTgwNTMyYjViMDVkZGU1NjdjNjEyMjBkOTM0MDZiN2UyMmU3JmRuPVJpY2srYW5kK01vcnR5K1NlYXNvbisyKyU1QldFQlJJUCU1RCslNUIxMDgwcCU1RCslNUJIRVZDJTVEJnRyPXVkcCUzQSUyRiUyRnRyYWNrZXIubGVlY2hlcnMtcGFyYWRpc2Uub3JnJTNBNjk2OSZ0cj11ZHAlM0ElMkYlMkZ6ZXIwZGF5LmNoJTNBMTMzNyZ0cj11ZHAlM0ElMkYlMkZ0cmFja2VyLmNvcHBlcnN1cmZlci50ayUzQTY5NjkmdHI9dWRwJTNBJTJGJTJGcHVibGljLnBvcGNvcm4tdHJhY2tlci5vcmclM0E2OTY5&affid=1337&imdb=" target="_blank" title="Play now using BitX"> 
       <img src="//thepiratebay.org/static/img/icons/icon-bitx.png" alt="Play link"> 
      </a> 
      <img src="//thepiratebay.org/static/img/icon_comment.gif" alt="This torrent has 7 comments." title="This torrent has 7 comments."> 
      <a href="/user/.BONE."> 
       <img src="//thepiratebay.org/static/img/vip.gif" alt="VIP" title="VIP" style="width:11px;" border='0'> 
      </a> 
      <font class="detDesc"> 
       Uploaded 11-03&nbsp;2015, Size 2.23&nbsp;GiB, ULed by 
       <a class="detDesc" href="/user/.BONE./" title="Browse .BONE."> 
        .BONE. 
       </a> 
      </font> 
     </td> 
     <td align="right">759</td> 
     <td align="right">130</td> 
    </tr> 
... 

あなたは後にしている部分がこれにSelectNodesでXPathパラメータを変更する//table[@id='searchResult']/tr/td/font[@class='detDesc']下にあり、かつInnerTextを出力し、あなたが後にしているものを提供します：

Uploaded 11-03 2015, Size 2.23 GiB, ULed by .BONE. 
Uploaded 07-26 2015, Size 2.98 GiB, ULed by Anonymous 
Uploaded 11-03 2015, Size 3.21 GiB, ULed by .BONE. 
Uploaded 10-12 2015, Size 5.07 GiB, ULed by ToyUp 
Uploaded 04-12 2014, Size 146.87 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 164.37 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 171.46 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 137.39 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 180.05 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 145.15 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 115.92 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 134.29 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 171.86 MiB, ULed by eztv 
Uploaded 04-12 2014, Size 141.65 MiB, ULed by eztv 
Uploaded 04-15 2014, Size 162.42 MiB, ULed by eztv 
Uploaded 04-15 2014, Size 5.78 GiB, ULed by frostyon420 
Uploaded 10-05 2015, Size 142.63 MiB, ULed by ettv 
Uploaded 07-02 2016, Size 4.62 GiB, ULed by AtaraxiaPrime 
Uploaded 08-24 2015, Size 143.38 MiB, ULed by TvTeam 
Uploaded 07-27 2015, Size 207.89 MiB, ULed by ettv 
Uploaded 07-28 2015, Size 941.23 MiB, ULed by frostyon420 
Uploaded 06-02 2014, Size 1.02 GiB, ULed by Minified 
Uploaded 09-21 2015, Size 455.91 MiB, ULed by EtHD 
Uploaded 04-18 2014, Size 5.24 GiB, ULed by nsj7762 
Uploaded 08-31 2015, Size 165.22 MiB, ULed by TvTeam 
Uploaded 06-28 2016, Size 8.69 GiB, ULed by fauxcon 
Uploaded 08-03 2015, Size 198.86 MiB, ULed by TvTeam 
Uploaded 08-03 2015, Size 190.11 MiB, ULed by punsher 
Uploaded 08-17 2015, Size 853.25 MiB, ULed by frostyon420 
Uploaded 09-28 2015, Size 399.73 MiB, ULed by Joker__TPB