Question

我有以下html页面：

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>

<head>
</head>

<body>
<div style="LEFT: 135; WIDTH: 450; POSITION: absolute; TOP: 70">
  <a name="content_begins"></a>
  <table cellSpacing="0" cellPadding="0" width="100%" border="0">
    <tr>
      <td vAlign="top">
      <table class="PortalGadget" cellSpacing="0" cellPadding="0" width="100%" border="0">
        <tr>
          <td>
          <table cellSpacing="6" cellPadding="0" border="0">
            <form name="authenticator" ACTION="auth-cup" METHOD="POST" ENCTYPE="application/x-www-form-urlencoded">
              <tr bgColor="#6c8899">
                <td><font face="Trebuchet MS" color="#ffffff">&nbsp;*** You Have Already Logged In ***</font></td>
              </tr>

              <tr height="20">
                <td vAlign="bottom" height="20">
                <font face="Trebuchet MS" size="-1">Context:</font></td>
              </tr>
              <tr>
                <td></td>
              </tr>
              <tr>
                <td vAlign="bottom" height="20">
                <font face="Trebuchet MS" size="-1">Username:</font></td>
              </tr>
              <tr>
                <td><input size="40" name="username"></td>
              </tr>
              <tr>
                <td><font face="Trebuchet MS" size="-1">Password:</font></td>
              </tr>
              <tr>
                <td><input type="password" size="40" name="password"></td>
              </tr>
              <tr>
                <td vAlign="bottom" height="20">
                <font face="Trebuchet MS" size="-1">Destination:</font></td>
              </tr>
              <tr>
                <td>
                <input size="40" name="url" value="http://ya.ru/"></td>
              </tr>
              <tr>
                <!---- Hidden field to identify forward/reverse proxy path ------>
                <input TYPE="hidden" NAME="proxypath" VALUE="forward">
              </tr>
              <tr>
                <td vAlign="bottom" align="left">
                <input type="submit" alt="Login" value="Login" border="0" name="loginButton">&nbsp;&nbsp;
                <input type="reset" alt="Reset" value="Reset"></td>
              </tr>
              <tr height="5">
                <td height="5"><hr SIZE="2"></td>
              </tr>
              <tr>
                <td><font face="Trebuchet MS" size="-1">
                <p>Copyright 1999-2003 Novell, Inc. All rights reserved.</p>
                </font></td>
              </tr>
            </form>
            </tbody>
          </table>
          </td>
        </tr>
      </table>
      </td>
    </tr>
  </table>
</div>
</body>
</html>

我想从td获得“你已经登录过”的文字。我有这段代码：

Stream str = SendData().GetResponseStream();
            HtmlAgilityPack.HtmlDocument doc = new HtmlAgilityPack.HtmlDocument();
            doc.Load(str);
            foreach (HtmlAgilityPack.HtmlNode table in doc.DocumentNode.SelectNodes("//table[@class='PortalGadget']"))
            {
                MessageBox.Show("Found: " + table.Id);
                foreach (HtmlAgilityPack.HtmlNode row in table.SelectNodes("//table"))
                {

                    HtmlAgilityPack.HtmlNodeCollection cells = row.SelectNodes("tr");

                    if (cells == null)
                    {
                        continue;
                    }

                    foreach (HtmlAgilityPack.HtmlNode cell in cells)
                    {
                        MessageBox.Show("cell: " + cell.InnerText);
                    }
                }
            }

但是我无法在代码中获得“你已经登录”的文字。如何在此场景中获取嵌套表格单元格值？

Answer 1

嗯，我发现解决方案似乎在我身上：

string value = doc.DocumentNode.SelectNodes("//table[@class='PortalGadget']/tr/td/table/tr/td")[0].InnerText;

Answer 2

要从另一个节点选择节点，您必须输入'。'在XPath的开头。

因此table.SelectNodes("//table")变为table.SelectNodes(".//table")

Answer 3

这实际上取决于你认为对这些数据有什么区别，但是当我看到HTML时，似乎将BGCOLOR设置为#ffffff的FONT元素是，所以这是相应的Html Agility Pack代码：

HtmlDocument doc = new HtmlDocument();
doc.Load(yourHtmlFile);
HtmlNode node = doc.DocumentNode.SelectSingleNode("//font[@color='#ffffff']");
Console.WriteLine(node.InnerText.Trim());

将输出：

&nbsp;*** You Have Already Logged In ***

使用HtmlAgilityPack获取嵌套表格单元格

3 个答案: