CanonicalizeUrl

The CanonicalizeUrl method is a utility function that canonicalizes a URL into a standard form to avoid duplicates. For example, "http://www.chilkatsoft.com/" and "http://www.chilkatsoft.com/default.asp" are the same URL.

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

// Does a DNS lookup to find the default domain, which may or may not include the "www." depending on the DNS results.
// Also domain names are converted to lowercase:
textBox1.Text += spider.CanonicalizeUrl("http://www.ChilkatSoft.com/") + "\r\n";
textBox1.Refresh();

// CanonicalizeUrl will drop the HTML fragment:
textBox1.Text += spider.CanonicalizeUrl("http://www.chilkatsoft.com/purchase2.asp#buyZip") + "\r\n";
textBox1.Refresh();

// If a username/password is in the URL, it gets dropped:
textBox1.Text += spider.CanonicalizeUrl("http://username:password@www.chilkatsoft.com/purchase2.asp#buyZip") + "\r\n";
textBox1.Refresh();

// Port 80 and 443 are dropped:
textBox1.Text += spider.CanonicalizeUrl("http://www.chilkatsoft.com:80/purchase2.asp") + "\r\n";
textBox1.Refresh();
textBox1.Text += spider.CanonicalizeUrl("https://www.paypal.com:443/") + "\r\n";
textBox1.Refresh();

// Removes default pages:
// default.asp, index.html, index.htm, default.html, index.htm, default.htm
// index.php, index.asp, default.php, .cfm, .aspx, ,php3, .pl, .cgi, .txt, .shtml, .phtml
textBox1.Text += spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.asp") + "\r\n";
textBox1.Refresh();
textBox1.Text += spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.asp") + "\r\n";
textBox1.Refresh();
textBox1.Text += spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.php") + "\r\n";
textBox1.Refresh();
textBox1.Text += spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.pl") + "\r\n";
textBox1.Refresh();
textBox1.Text += spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.htm") + "\r\n";
textBox1.Refresh();

// Output:
// http://chilkatsoft.com/
// http://chilkatsoft.com/purchase2.asp
// http://chilkatsoft.com/purchase2.asp
// http://chilkatsoft.com/purchase2.asp
// https://www.paypal.com/
// http://chilkatsoft.com/
// http://chilkatsoft.com/
// http://chilkatsoft.com/
// http://chilkatsoft.com/
// http://chilkatsoft.com/