C#使用Html Agility Pack（HAP）的XPath解析HTML

标签：XPath htmlDoc Agility Console html HTML var using public

安装

Html Agility Pack（HAP）是C#的开源项目，支持XPath查询。

官网：https://html-agility-pack.net/

使用NuGet安装，如图：

C#使用Html Agility Pack（HAP）的XPath解析HTML_linq

HtmlDocument.Load加载文件

using System;
using HtmlAgilityPack;

public class Program
{
    public static void Main()
    {
        SaveHtmlFile();
        var path = @"test.html";
        var doc = new HtmlDocument();
        doc.Load(path);
        var node = doc.DocumentNode.SelectSingleNode("//body");
        Console.WriteLine(node.OuterHtml);
    }

    private static void SaveHtmlFile()
    {
        var html =
        @"<!DOCTYPE html>
        <html>
        <body>
            <h1>This is <b>bold</b> heading</h1>
            <p>This is <u>underlined</u> paragraph</p>
            <h2>This is <i>italic</i> heading</h2>
        </body>
        </html> ";
        var htmlDoc = new HtmlDocument();
        htmlDoc.LoadHtml(html);
        htmlDoc.Save("test.html");
    }
}

C#使用Html Agility Pack（HAP）的XPath解析HTML_c#_02

HtmlDocument.LoadHtml加载字符串

using System;
using HtmlAgilityPack;

public class Program
{
    public static void Main()
    {
        var html = @"<!DOCTYPE html>
        <html>
        <body>
            <h1>This is <b>bold</b> heading</h1>
            <p>This is <u>underlined</u> paragraph</p>
            <h2>This is <i>italic</i> heading</h2>
        </body>
        </html> ";

        var htmlDoc = new HtmlDocument();
        htmlDoc.LoadHtml(html);
        var htmlBody = htmlDoc.DocumentNode.SelectSingleNode("//body");
        Console.WriteLine(htmlBody.OuterHtml);
    }
}

C#使用Html Agility Pack（HAP）的XPath解析HTML_c#_03

HtmlWeb.Load通过URL加载HTML

using HtmlAgilityPack;
using System;

namespace ConsoleApp1
{
    class Program
    {
        static void Main(string[] args)
        {
            var html = @"https://www.baidu.com/";
            var web = new HtmlWeb();
            var doc = web.Load(html);
            var node = doc.DocumentNode.SelectSingleNode("//head/title");
            Console.WriteLine(node.OuterHtml);
        }
    }
}

SelectNodes()选择多个节点

// @nuget: HtmlAgilityPack

using System;
using System.Linq;
using HtmlAgilityPack;

public class Program
{
    public static void Main()
    {
        var html =
        @"<TD class=texte width=""50%"">
            <DIV align=right>Name :<B> </B></DIV>
        </TD>
        <TD width=""50%"">
            <INPUT class=box value=John maxLength=16 size=16 name=user_name>
            <INPUT class=box value=Tony maxLength=16 size=16 name=user_name>
            <INPUT class=box value=Jams maxLength=16 size=16 name=user_name>
        </TD>
        <TR vAlign=center>";

        var htmlDoc = new HtmlDocument();
        htmlDoc.LoadHtml(html);

        string name = htmlDoc.DocumentNode
                        .SelectNodes("//td/input")
                        .First()
                        .Attributes["value"].Value;

        Console.WriteLine(name);
    }
}

SelectSingleNode(String)选择第一个节点

// @nuget: HtmlAgilityPack

using System;

using HtmlAgilityPack;

public class Program
{
  public static void Main()
  {
    var html =
    @"<TD class=texte width=""50%"">
      <DIV align=right>Name :<B> </B></DIV>
    </TD>
    <TD width=""50%"">
        <INPUT class=box value=第一 maxLength=16 size=16 name=user_name>
        <INPUT class=box value=第二 maxLength=16 size=16 name=user_name>
        <INPUT class=box value=第三 maxLength=16 size=16 name=user_name>
    </TD>
    <TR vAlign=center>";

    var htmlDoc = new HtmlDocument();
    htmlDoc.LoadHtml(html);

    string name = htmlDoc.DocumentNode
      .SelectSingleNode("//td/input")
      .Attributes["value"].Value;

    Console.WriteLine(name);
  }
}

获取属性

// @nuget: HtmlAgilityPack

using System;
using System.Xml;
using HtmlAgilityPack;

public class Program
{
    public static void Main()
    {
        var html =
        @"<body>
            <h1>This is <b>bold</b> heading</h1>
            <p>This is <u>underlined</u> paragraph</p>
            
            <h1>This is <i>italic</i> heading</h1>
            <p>This is <u>underlined</u> paragraph</p>
        </body>";

        var htmlDoc = new HtmlDocument();
        htmlDoc.LoadHtml(html);

        var htmlNodes = htmlDoc.DocumentNode.SelectNodes("//body/h1");

        foreach (var node in htmlNodes)
        {
            Console.WriteLine("InnerHtml:" + node.InnerHtml);
            Console.WriteLine("OuterHtml:" + node.OuterHtml);
            Console.WriteLine("InnerText:"+node.InnerText);
            Console.WriteLine("ParentNode" + node.ParentNode.Name);
            Console.WriteLine("===========");
        }
    }
}

C#使用Html Agility Pack（HAP）的XPath解析HTML_加载_04

参考

https://html-agility-pack.net/parser

标签：XPath,htmlDoc,Agility,Console,html,HTML,var,using,public
From： https://blog.51cto.com/lilongsy/5785892