Question

This is a followup of a previous question I had.

I got the very excellent link parsing code from here.

所以我有以下形式的HTML：

<html>
    <head>
        RANDOM JAVASCRIPT AND CSS AHHHHHH!!!!!!!!
    </head>
    <body>
        <a href="/Random/link/here">Random</a>
        <a href="/Random/link/here">Random</a>
        <a href="/Random/link/here">Random</a>
        <a href="/Random/link/here">Random</a>
        <a href="/Random/link/here">Random</a>
        <a href="/Random/link/here">Random</a>
        <table class="table">
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
            <tr><a href="/subdir/members/Name">Name</a></tr>
        </table>
    <body>
</html>

我有以下代码，目的是提取其中包含的信息，然后从该信息中提取链接：

public class MainClass
{
    public static void Main(String[] args)
    {
        string url = args[1];
        Extractinfo pageScrape = new Extractinfo();
        pageScrape.RenderPage(url);
    }
}
public class Extractinfo
{
    public HtmlDocument RenderPage(string url)
    {
        try
        {
                HtmlDocument pageSource = new HtmlDocument();
                var webGet = new HtmlWeb();
                pageSource = webGet.Load(url);

                ExtractLinks(pageSource);
        }
        catch (WebException e)
        {
            Console.WrtieLine(e.Message + ": " + e.StackTrace);
        }
    }

    private List<string> ExtractHrefTags(HtmlNode htmlSnippet)
        {
            List<string> hrefTags = new List<string>();

            foreach (HtmlNode link in htmlSnippet.SelectNodes("//a[@href]"))
            {
                HtmlAttribute att = link.Attributes["href"];
                hrefTags.Add(att.Value);
            }

            return hrefTags;
        }

        public void ExtractLinks(HtmlDocument pagesource)
        {

            var elements = pagesource.DocumentNode.SelectNodes("//table[@class='table']");
            List<string> hrefTags = new List<string>();
            foreach (var ele in elements)
            {
                 hrefTags = ExtractHrefTags(ele);
            }
        }
    }
}

现在，不是只获取<table class="table>*****</table>内部的链接，而是将此页面上的所有链接放入List hreftags。我在这做错了什么？如何修复错误，以便提取的唯一链接是<table class="table>*****</table>内的链接？

感谢您的帮助！

Answer 1

您需要添加“。”到您的XPath以匹配表的子节点，如下所示：

htmlSnippet.SelectNodes(".//a[@href]")

尝试使用htmlagiliypack从htmlnode中提取链接时遇到问题

1 个答案: