.NET Core(C#) AngleSharp 解析百度和谷歌搜索结果html(链接、标题、描述)

本文主要介绍.NET Core中，使用AngleSharp解析百度和谷歌的结果的html代码，提取出结果列表中的标题，文章的链接和描述的方法，以及相关的示例代码。

1､项目中安装引用AngleSharp

AngleSharp：http://anglesharp.github.io/

1）使用Nuget管理控制台

将AngleSharp集成到项目中的最简单方法是使用NuGet。您可以通过打开包管理器控制台（PM）并键入以下语句来安装AngleSharp：

Install-Package AngleSharp

2）使用Nuget图形管理器

使用Nuget的界面的管理器搜索"AngleSharp"=> 找到点出点击"安装"。

3）使用.NET CLI命令安装

> dotnet add TodoApi.csproj package AngleSharp

相关文档：VS(Visual Studio)中Nuget的使用

2､提取解析百度的搜索结果的html

public static List GetBaiduResult(string wd, int p){    if (p <= 0) p = 1;    string url = string.Format("https://www.baidu.com/s?wd={0}&pn={1}", Uri.EscapeDataString(wd), (p - 1) * 10);    var requester = new DefaultHttpRequester("Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36");    requester.Headers.Add("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8");    requester.Headers.Add("Referer", "");    requester.Headers.Add("Accept-Language", "zh-Hans-CN,zh-Hans;q=0.8,en-US;q=0.5,en;q=0.3");    var context = BrowsingContext.New(Configuration.Default.WithLocaleBasedEncoding().WithDefaultLoader().WithDefaultCookies().With(requester));    //根据虚拟请求/响应模式创建文档    var document = context.OpenAsync(url).Result;    //var blueListItemsLinq = document.All.Where(m => m.LocalName == "li" && m.ClassList.Contains("blue"));    //或者直接使用CSS选择器    var itemsCssSelector = document.QuerySelectorAll("#content_left .result");    List results = new List();    foreach (var item in itemsCssSelector)    {        if (item.QuerySelector("h3 a") == null ||            item.QuerySelector("h3 a") == null ||            item.QuerySelector("div.c-abstract") == null ||            item.QuerySelector("div.f13 a.c-showurl") == null ||            item.QuerySelector("div.f13 a.m") == null            )        {            continue;        }        /*  Console.WriteLine("title = " + item.QuerySelector("h3 a").Html());          Console.WriteLine("href = " + item.QuerySelector("h3 a").GetAttribute("href"));          Console.WriteLine("desc = " + item.QuerySelector("div.c-abstract").Html());          Console.WriteLine("a = " + item.QuerySelector("div.f13  a.c-showurl").Html());          Console.WriteLine("a_herf = " + item.QuerySelector("div.f13  a.c-showurl").GetAttribute("href"));          Console.WriteLine("kz = " + item.QuerySelector("div.f13  a.m").GetAttribute("href"));*/        results.Add(new SearchResult()        {            title = item.QuerySelector("h3 a").Html(),            desc = item.QuerySelector("div.c-abstract").Html(),            url = item.QuerySelector("h3 a").GetAttribute("href"),            urlText = item.QuerySelector("div.f13  a.c-showurl").Html(),            snapshot = item.QuerySelector("div.f13  a.m").GetAttribute("href")        });    }    return results;}

3､提取解析谷歌的搜索结果的html

public static List GetGoogleResult(string wd, int p) {     if (p <= 0) p = 1;     string url = string.Format("https://www.google.com/search?q={0}&start={1}", Uri.EscapeDataString(wd), (p - 1) * 10);     var requester = new DefaultHttpRequester("Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36");     requester.Headers.Add("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8");     requester.Headers.Add("Referer", "");     requester.Headers.Add("Accept-Language", "zh-Hans-CN,zh-Hans;q=0.8,en-US;q=0.5,en;q=0.3");     var context = BrowsingContext.New(Configuration.Default.WithLocaleBasedEncoding().WithDefaultLoader().WithDefaultCookies().With(requester));     //根据虚拟请求/响应模式创建文档     var document = context.OpenAsync(url).Result;     //var blueListItemsLinq = document.All.Where(m => m.LocalName == "li" && m.ClassList.Contains("blue"));     //或者直接使用CSS选择器     var itemsCssSelector = document.QuerySelectorAll("#rso > div");     List results = new List();     foreach (var item in itemsCssSelector)     {         try         {             //Console.WriteLine("title = " + item.QuerySelector("div > div.r > a > h3").Html());             //Console.WriteLine("href = " + item.QuerySelector("div > div.r > a").GetAttribute("href"));             //Console.WriteLine("desc = " + item.QuerySelector("div > div.s > div").Html());             //Console.WriteLine("a = " + item.QuerySelector("div > div.r > a > div > cite").Html());             //Console.WriteLine("a_herf = " + item.QuerySelector("div.f13  a.c-showurl").GetAttribute("href"));             // Console.WriteLine("kz = " + item.QuerySelector("div > div.r > div > div.eFM0qc > span > div > ol > li > a").GetAttribute("href"));             if (item.QuerySelector("div > div.r > a > h3") == null ||                 item.QuerySelector("div > div.s > div") == null ||                 item.QuerySelector("div > div.r > a") == null ||                 item.QuerySelector("div > div.r > a > div > cite") == null ||                 item.QuerySelector("div > div.r > div > div.eFM0qc > span > div > ol > li > a") == null                 )             {                 continue;             }             results.Add(new SearchResult()             {                 title = item.QuerySelector("div > div.r > a > h3").Html(),                 desc = item.QuerySelector("div > div.s > div").Html(),                 url = item.QuerySelector("div > div.r > a").GetAttribute("href"),                 urlText = item.QuerySelector("div > div.r > a > div > cite").Html(),                 snapshot = item.QuerySelector("div > div.r > div > div.eFM0qc > span > div > ol > li > a").GetAttribute("href")             });         }         catch (Exception ex)         {             log.Error(ex);         }     }     return results; }