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.

Download Chilkat Spider ActiveX

' The Chilkat Spider component/library is free.
Dim spider As New 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:
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.ChilkatSoft.com/") & vbCrLf

' CanonicalizeUrl will drop the HTML fragment:
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.chilkatsoft.com/purchase2.asp#buyZip") & vbCrLf

' If a username/password is in the URL, it gets dropped:
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://username:password@www.chilkatsoft.com/purchase2.asp#buyZip") & vbCrLf

' Port 80 and 443 are dropped:
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.chilkatsoft.com:80/purchase2.asp") & vbCrLf
Text1.Text = Text1.Text & spider.CanonicalizeUrl("https://www.paypal.com:443/") & vbCrLf

' 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
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.asp") & vbCrLf
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.asp") & vbCrLf
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.php") & vbCrLf
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.pl") & vbCrLf
Text1.Text = Text1.Text & spider.CanonicalizeUrl("http://www.chilkatsoft.com/index.htm") & vbCrLf

' 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/