.NET 快速实现网页数据抓取

namespace DotnetSpiderExercise{    public class RecommendedRankingModel    {        /// <summary>        /// 文章标题        /// </summary>        public string ArticleTitle { get; set; }
        /// <summary>        /// 文章简介        /// </summary>        public string ArticleSummary { get; set; }
        /// <summary>        /// 文章地址        /// </summary>        public string ArticleUrl { get; set; }    }}

using DotnetSpider.DataFlow.Parser;using DotnetSpider.DataFlow;using DotnetSpider.Downloader;using DotnetSpider.Http;using DotnetSpider.Scheduler.Component;using DotnetSpider.Selector;using DotnetSpider;using Microsoft.Extensions.Logging;using Microsoft.Extensions.Options;using Serilog;using DotnetSpider.Scheduler;using Microsoft.Extensions.Hosting;using System.Reflection;
namespace DotnetSpiderExercise{    public class RecommendedRankingSpider : Spider    {        public RecommendedRankingSpider(IOptions<SpiderOptions> options,            DependenceServices services,            ILogger<Spider> logger) : base(options, services, logger)        {        }
        public static async Task RunAsync()        {            var builder = Builder.CreateDefaultBuilder<RecommendedRankingSpider>();            builder.UseSerilog();            builder.UseDownloader<HttpClientDownloader>();            builder.UseQueueDistinctBfsScheduler<HashSetDuplicateRemover>();            await builder.Build().RunAsync();        }
        protected override async Task InitializeAsync(CancellationToken stoppingToken = default)        {            //添加自定义解析            AddDataFlow(new Parser());            //使用控制台存储器            AddDataFlow(new ConsoleStorage());            //添加采集请求:博客园10天推荐排行榜            await AddRequestsAsync(new Request("https://www.cnblogs.com/aggsite/topdiggs")            {                //请求超时10秒                Timeout = 10000            });        }
        class Parser : DataParser        {            public override Task InitializeAsync()            {                return Task.CompletedTask;            }
            protected override Task ParseAsync(DataFlowContext context)            {                var recommendedRankingList = new List<RecommendedRankingModel>();                // 网页数据解析                var number = 1;                var recommendedList = context.Selectable.SelectList(Selectors.XPath(".//article[@class='post-item']"));                foreach (var news in recommendedList)                {                    var articleTitle = news.Select(Selectors.XPath(".//a[@class='post-item-title']"))?.Value;                    var articleSummary = news.Select(Selectors.XPath(".//p[@class='post-item-summary']"))?.Value?.Replace("\n", "").Replace(" ", "");                    var articleUrl = news.Select(Selectors.XPath(".//a[@class='post-item-title']/@href"))?.Value;
                    Console.WriteLine($"第{number}篇文章 标题：{articleTitle}");
                    recommendedRankingList.Add(new RecommendedRankingModel                    {                        ArticleTitle = articleTitle,                        ArticleSummary = articleSummary,                        ArticleUrl = articleUrl                    });
                    number++;                }
                using (StreamWriter sw = new StreamWriter("RecommendedRanking.txt"))                {                    foreach (RecommendedRankingModel model in recommendedRankingList)                    {                        string line = $"文章标题：{model.ArticleTitle}\r\n文章简介：{model.ArticleSummary}\r\n文章地址：{model.ArticleUrl}";                        sw.WriteLine(line + "\r\n ========================================================================================== \r\n");                    }                }                return Task.CompletedTask;            }        }    }}

namespace DotnetSpiderExercise{    public class Program    {        static async Task Main(string[] args)        {            Console.WriteLine("网页数据抓取开始...");
            await RecommendedRankingSpider.RunAsync();
            Console.WriteLine("网页数据抓取完成...");        }    }}