(Delphi ActiveX) Avoid URLs Matching Any of a Set of Patterns

Demonstrates how to use "avoid patterns" to prevent spidering any URL that matches a wildcarded pattern. This example avoids URLs containing the substrings "java", "python", or "perl".

Chilkat for Delphi Downloads Chilkat ActiveX DLL for Delphi Chilkat non-ActiveX DLL for Delphi * The examples here use the ActiveX DLL.

uses
    Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
    Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls, Chilkat_TLB;

...

procedure TForm1.Button1Click(Sender: TObject);
var
spider: TChilkatSpider;
i: Integer;
success: Integer;

begin
spider := TChilkatSpider.Create(Self);

// The spider object crawls a single web site at a time.  As you'll see
// in later examples, you can collect outbound links and use them to 
// crawl the web.  For now, we'll simply spider 10 pages of chilkatsoft.com
spider.Initialize('www.chilkatsoft.com');

// Add the 1st URL:
spider.AddUnspidered('http://www.chilkatsoft.com/');

// Avoid URLs matching these patterns:
spider.AddAvoidPattern('*java*');
spider.AddAvoidPattern('*python*');
spider.AddAvoidPattern('*perl*');

// Begin crawling the site by calling CrawlNext repeatedly.

for i := 0 to 9 do
  begin

    success := spider.CrawlNext();
    if (success = 1) then
      begin
        // Show the URL of the page just spidered.
        Memo1.Lines.Add(spider.LastUrl);
        // The HTML is available in the LastHtml property
      end
    else
      begin
        // Did we get an error or are there no more URLs to crawl?
        if (spider.NumUnspidered = 0) then
          begin
            Memo1.Lines.Add('No more URLs to spider');
          end
        else
          begin
            Memo1.Lines.Add(spider.LastErrorText);
          end;
      end;
    // Sleep 1 second before spidering the next URL.
    spider.SleepMs(1000);
  end;
end;