我要檢索的寬度和html元素的高度與HtmlAgilityPack

Question

如何與HtmlAgilityPack檢索img元素的寬度和高度，我這樣做是這樣的..

HtmlAgilityPack.HtmlAttribute width = link.Attributes["width"]; 
    HtmlAgilityPack.HtmlAttribute height = link.Attributes["height"]; 

，但寬度和高度是最病例爲空。如何獲得CSS的高度和寬度？

Answer 1

Basead在本頁面：page

public sealed class UtilParserHTML 
{ 

    //Private Fields 
    private Uri Uri; 
    private Stream StreamPage; 
    private HttpWebRequest HttpRequest; 
    private HttpWebResponse HttpResponse; 

    //Public Fields 
    public HtmlDocument HtmlDocument { private set; get; } 

    public UtilParserHTML() 
    { 
     if (this.HtmlDocument == null) 
      HtmlDocument = new HtmlDocument(); 
    } 

    public void LoadHTMLPage(string UrlPage) 
    { 
     if (string.IsNullOrEmpty(UrlPage)) 
      throw new ArgumentNullException(""); 

     CookieContainer cookieContainer = new CookieContainer(); 

     this.Uri = new Uri(UrlPage); 
     this.HttpRequest = (HttpWebRequest)WebRequest.Create(UrlPage); 
     this.HttpRequest.Method = WebRequestMethods.Http.Get;  
     this.HttpRequest.CookieContainer = cookieContainer; 
     this.HttpResponse = (HttpWebResponse)this.HttpRequest.GetResponse(); 
     this.StreamPage = this.HttpResponse.GetResponseStream(); 
     this.HtmlDocument.Load(StreamPage); 
    } 

    public void LoadHTMLPage(FileStream StreamPage) 
    { 
     if (StreamPage == null) 
      throw new ArgumentNullException(""); 

     HtmlDocument.Load(StreamPage); 
    } 

    public HtmlNodeCollection GetNodesByExpression(string XPathExpression) 
    { 
     if (string.IsNullOrEmpty(XPathExpression)) 
      throw new ArgumentNullException(""); 

     return this.HtmlDocument.DocumentNode.SelectNodes(XPathExpression); 
    } 

使用XPath在HTML瀏覽。 在這種情況下我用這個XPath表達式：// DIV [@類= 'arrowRibbon'] // IMG

查找： ...

this.ParserHTML.LoadHTMLPage("http://www.img.com.br/default.aspx"); 
      HtmlNodeCollection HtmlNodeCollectionResult = this.ParserHTML.GetNodesByExpression(Page.XPathExpression); 

      if (HtmlNodeCollectionResult != null) 
      { 
       foreach (HtmlNode NodeResult in HtmlNodeCollectionResult) 
       { 
        var src = NodeResult.Attributes["src"].Value; 
       } 
      } 

...

EDIT

查找與寬度和高度這個完整的例子：

this.ParserHTML.LoadHTMLPage("http://www.w3schools.com/tags/tag_img.asp"); 
      HtmlNodeCollection HtmlNodeCollectionResult = this.ParserHTML.GetNodesByExpression("//div[@class='tryit_ex'] //img"); 

      if (HtmlNodeCollectionResult != null) 
      { 
       foreach (HtmlNode NodeResult in HtmlNodeCollectionResult) 
       { 
        var src = NodeResult.Attributes["src"].Value; 
        var w = NodeResult.Attributes["width"].Value; 
        var h = NodeResult.Attributes["height"].Value; 
       } 
      } 

希望得到這個幫助。