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".

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//  The Chilkat Spider component/library is free.
Chilkat.Spider spider = new Chilkat.Spider();

//  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.
int i;
for (i = 0; i <= 9; i++) {
    bool success;
    success = spider.CrawlNext();
    if (success == true) {
        //  Show the URL of the page just spidered.
        textBox1.Text += spider.LastUrl + "\r\n";
        //  The HTML is available in the LastHtml property
    }
    else {
        //  Did we get an error or are there no more URLs to crawl?
        if (spider.NumUnspidered == 0) {
            MessageBox.Show("No more URLs to spider");
        }
        else {
            MessageBox.Show(spider.LastErrorText);
        }

    }

    //  Sleep 1 second before spidering the next URL.
    spider.SleepMs(1000);
}