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c#asp.nethtmlhtml-agility-packhttpmodule

agility html parser read from buffer/stream


I am trying to alter an HTML page before it renders in a browser using an HTTP module. I tried to implement the agility HTML parser, but it only seems to read from files.

How can I have it read from a buffer/stream?

public override void Write(byte[] buffer, int offset, int count)
    {
      byte[] data = new byte[count];
      Buffer.BlockCopy(buffer, offset, data, 0, count);
      string html = System.Text.Encoding.Default.GetString(buffer);

      HtmlDocument doc = new HtmlDocument();
      doc.Load(html);
      foreach(HtmlNode link in doc.DocumentElement.SelectNodes("//a[@href"])
      {
      HtmlAttribute att = link["href"];
      att.Value = FixLink(att);
      }
    }

Solution

  • You should be able to use a MemoryStream to read in the data:

    public override void Write(byte[] buffer, int offset, int count)
    {
      var stream = new MemoryStream(buffer, offset, count);
    
      HtmlDocument doc = new HtmlDocument();
      doc.Load(stream);
    
      foreach(HtmlNode link in doc.DocumentElement.SelectNodes("//a[@href"])
      {
        HtmlAttribute att = link["href"];
        att.Value = FixLink(att);
      }
    }