(VB.NET) 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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Dim spider As 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.
Dim i As Integer
For i = 0 To 9
    Dim success As Boolean
    success = spider.CrawlNext()
    If (success = True) Then
        ' Show the URL of the page just spidered.
        Debug.WriteLine(spider.LastUrl)
        ' 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) Then
            Debug.WriteLine("No more URLs to spider")
        Else
            Debug.WriteLine(spider.LastErrorText)
        End If

    End If

    ' Sleep 1 second before spidering the next URL.
    spider.SleepMs(1000)
Next