C# HtmlDocument.QuerySelector方法代码示例

        public static ComicParseResult Parse(string html)
        {
            if (html == null) throw new ArgumentNullException(nameof(html));
            if (html == "") throw new ArgumentException($"{nameof(html)} should contain some text", nameof(html));

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

            var img = doc.QuerySelectorAll("img.strip")
                .FirstOrDefault(s => !s.Attributes.Contains("width"));
            if (img == null)
                return ComicParseResult.Fail("Could not find strip url");

            var src = img.GetAttributeValue("src", null);
            if (src == null)
                return ComicParseResult.Fail("img element did not have src attribute");

            var meta = doc.QuerySelector("meta[name='twitter:url']");
            if (meta == null)
                return ComicParseResult.Fail("Could not load twitter:url attribtue");

            var content = meta.GetAttributeValue("content", null);
            if (content == null)
                return ComicParseResult.Fail("meta tag did not have content attribute");

            var dateString = content.Replace("http://www.gocomics.com/pearlsbeforeswine/", "");

            var date = DateTime.ParseExact(dateString, "yyyy/MM/dd", CultureInfo.InvariantCulture);
            var uri = new Uri(src);

            return ComicParseResult.Succeed(uri, date);
        }

        public static ComicParseResult Parse(string html)
        {
            if (html == null)
                throw new ArgumentNullException(nameof(html));

            if (string.IsNullOrEmpty(html))
                throw new ArgumentException("html is empty", nameof(html));

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

            var image = doc.GetElementbyId("main-comic");
            if (image == null)
            {
                return ComicParseResult.Fail("Could not find comic img element");
            }

            var dateNode = doc.QuerySelector(".past-week-comic-title");
            if (dateNode == null)
            {
                return ComicParseResult.Fail("Could not find date elemenet");
            }

            DateTime date;
            if (!DateTime.TryParseExact(dateNode.InnerText, "yyyy.MM.dd", CultureInfo.InvariantCulture, DateTimeStyles.None, out date))
            {
                return ComicParseResult.Fail($"Could not parse date: '{dateNode.InnerText}'");
            }

            var src = EnsureHttp(image.Attributes["src"].Value);

            return ComicParseResult.Succeed(src, date);
        }

        public static ComicParseResult Parse(string html)
        {
            if (html == null) throw new ArgumentNullException(nameof(html));
            if (html == "") throw new ArgumentException("html must have some contents", nameof(html));

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

            var img = doc.QuerySelector(".img-comic");
            var src = img?.GetAttributeValue("src", null);

            var meta = doc.QuerySelector("meta[property='article:publish_date']");
            var date = meta?.GetAttributeValue("content", null);

            if (src == null)
                return ComicParseResult.Fail("Could not find image src");
            if (date == null)
                return ComicParseResult.Fail("Could not find publish date");

            return ComicParseResult.Succeed(new Uri(src), DateTime.Parse(date));
        }

        public string GetCategory(HtmlDocument doc)
        {
            try
            {

                HtmlNode node = doc.QuerySelector("[data-ng-bind~=category]");
                return node.InnerText;
            }
            catch (Exception e)
            {
                _logger.Error("Get Category",e);
                return "";
            }
        }

        public string GetStrainUrl(HtmlDocument doc)
        {
            try
            {

                HtmlNode node = doc.QuerySelector("a.strain-link");
                var url = node.Attributes["href"];
                return url.Value;
            }
            catch (Exception e)
            {
                _logger.Error("Get Strain URL", e);
                return "";
            }
        }

        public decimal GetRating(HtmlDocument doc)
        {
            try
            {

                HtmlNode node = doc.QuerySelector("span[star-rating]");
                var rating = node.Attributes["star-rating"];
                return Decimal.Parse(rating.Value);
            }
            catch (Exception e)
            {
                _logger.Error("Get Rating",e);
                return -1;
            }
        }

        public void ContentHasImageTagWithSource()
        {
            var feed = new ComicFeed("Foobar", new Uri("http://abc.def"));

            var xml = feed.Render(new[]
            {
                new Comic()
                {
                    Permalink = "http://www.google.com/",
                    ImageSrc = "http://example.com/image.png"
                }
            });

            var rss = ReadRssXml(xml);
            var doc = new HtmlDocument();
            doc.LoadHtml(rss.Items.First().Summary.Text);
            var img = doc.QuerySelector("img");

            Check.That(img.GetAttributeValue("src", null)).IsEqualTo("http://example.com/image.png");
        }

        public string GetReview(HtmlDocument doc)
        {
            try
            {

                HtmlNode node = doc.QuerySelector("div.m-review > div.padding-rowItem--xl .notranslate");
                return node.InnerText;
            }
            catch (Exception e)
            {
                _logger.Error("Get Review", e);
                return "";
            }
        }

 public string GetStrainTitle(HtmlDocument doc)
 {
     try{
         HtmlNode node = doc.QuerySelector("[data-ng-bind-html~=name]");
         return node.InnerText;  
     }
     catch (Exception e)
     {
         _logger.Error("Get Strain Title",e);
         return "";
     }
 }