Html Agility Pack SelectSingleNode在迭代中总是给出相同的结果？ [英] Html Agility Pack SelectSingleNode giving always same result in iteration?

问题描述

我想要集合中的节点，但迭代SelectSingleNode我不断获取相同的对象，只是node.Id正在改变...
我所尝试的是读出给定网站的web响应并获取一些信息如特殊定义元素中的值，链接..

  int offSet = 0; 
 string address =http://www.testsite.de/ergebnisliste.html?offset=+ offSet; 
 
 HtmlWeb web = new HtmlWeb（）; 
 //web.OverrideEncoding = Encoding.UTF8; 
 HtmlDocument doc = web.Load（address）; 
 
 HtmlNodeCollection collection = doc.DocumentNode.SelectNodes（//div[@itemtype='http://schema.org/Posting']）; 
 
 foreach（集合中的HtmlNode节点）{
 string id = HttpUtility.HtmlDecode（node.Id）; 
 string cpname = HttpUtility.HtmlDecode（node.SelectSingleNode（// span [@ itemprop ='name']）。InnerText）; 
 string cptitle = HttpUtility.HtmlDecode（node.SelectSingleNode（// span [@ itemprop ='title']）。InnerText）; 
 string cpaddress = HttpUtility.HtmlDecode（node.SelectSingleNode（// span [@ itemprop ='addressLocality']）。InnerText）; 
 string date = HttpUtility.HtmlDecode（node.SelectSingleNode（// div [@ itemprop ='datePosted']）。InnerText）; 
 string link =http://www.testsite.de+ HttpUtility.HtmlDecode（node.SelectSingleNode（// div [@ class ='h3 title'] // a [@href]）。 GetAttributeValue（href，default））; 
} 
  

例如1次迭代：

 < div id =66666itemtype =http://schema.org/Posting> 
< div> 
< a> 
< img /> 
< / a> 
< / div> 
< div> 
< div class =h3 title> 
< a href =/ test.htmltitle =测试> 
< span itemprop =title>测试< / span> 
< / a> 
< / div> 
< div> 
< span itemprop =name> TestName< / span> 
< / div> 
< / div> 
< div> 
< div> 
< div> 
< div> 
< span itemprop =地址>测试< / span> 
< / div> 
< span> 
< a> 
< span><！ -   - >< / span> 
< span>< / span> 
< / a> 
< / span> 
< / div> 
< / div> 
< div itemprop =date> 
< time datetime =2013-03-01> 01.03.13< / time> 
< / div> 
< / div> 
  

解决方案

通过编写

node.SelectSingleNode（// span [@ itemprop ='name']）。InnerText $ b $ p $就像你写的那样
$ b $ doc.DocumentNode.SelectSingleNode（ // @ span [@ itemprop ='name']）。InnerText

要做你想做的事情，你应该写这个： node.SelectSingleNode（.// span [@ itemprop ='name']）。InnerText 。
$ b 这个。点/周期告诉在当前节点上搜索节点而不是 doc

I would like the nodes in the collection but with iterating SelectSingleNode I keep getting the same object just node.Id is changing... What i try is to readout the webresponse of a given site and catch some information like values, links .. in special defined elements.

int offSet = 0;
string address = "http://www.testsite.de/ergebnisliste.html?offset=" + offSet;

HtmlWeb web = new HtmlWeb();
//web.OverrideEncoding = Encoding.UTF8;
HtmlDocument doc = web.Load(address);

HtmlNodeCollection collection = doc.DocumentNode.SelectNodes("//div[@itemtype='http://schema.org/Posting']");

foreach (HtmlNode node in collection) {
    string id = HttpUtility.HtmlDecode(node.Id);
    string cpname = HttpUtility.HtmlDecode(node.SelectSingleNode("//span[@itemprop='name']").InnerText);
    string cptitle = HttpUtility.HtmlDecode(node.SelectSingleNode("//span[@itemprop='title']").InnerText);
    string cpaddress = HttpUtility.HtmlDecode(node.SelectSingleNode("//span[@itemprop='addressLocality']").InnerText);
    string date = HttpUtility.HtmlDecode(node.SelectSingleNode("//div[@itemprop='datePosted']").InnerText);
    string link = "http://www.testsite.de" + HttpUtility.HtmlDecode(node.SelectSingleNode("//div[@class='h3 title']//a[@href]").GetAttributeValue("href", "default"));               
}

This is for example for 1 iteration:

<div id="66666" itemtype="http://schema.org/Posting">   
<div>
    <a>
        <img />
    </a>
</div>
<div>
    <div class="h3 title">
        <a href="/test.html"  title="Test">
            <span itemprop="title">Test</span>
        </a>
    </div>
    <div>
        <span itemprop="name">TestName</span>       
    </div>
</div>
<div>
    <div>
        <div>
            <div>
                <span itemprop="address">Test</span>
            </div>
            <span>                     
                <a>
                    <span><!-- --></span>
                    <span></span>
                </a>
            </span>         
        </div>
    </div>      
    <div itemprop="date">
        <time datetime="2013-03-01">01.03.13</time>
    </div>
</div>

解决方案

By writing

node.SelectSingleNode("//span[@itemprop='name']").InnerText

it's like you writing

doc.DocumentNode.SelectSingleNode("//span[@itemprop='name']").InnerText

To do what you want to do you should write it like this: node.SelectSingleNode(".//span[@itemprop='name']").InnerText.

This .dot / period tells make a search on the current node which is node instead on doc

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