how can htmlagilitypack check if nodes exist on webpage?

html-agility-pack

Question

Using Vb.net and HtmlAgilityPack is there a way to check if the node exists on the webpage before selecting the node ?

While running my program, if the node doesn't exist at all on the page, I am getting a null exception error message.

I don't want to use 

If firsttag(0).InnerText IsNot Nothing Then

as by using this, the program is already trying to get the value of the node.

I would like to scan the webpage first to see if the node exists 

Dim firsttag As HtmlAgilityPack.HtmlNodeCollection = docnews.DocumentNode.SelectNodes("//div[(@class='byline')]")

Is there anything like 

if firsttage(0) search does not exist then Continue For Else
1
0
1/4/2014 5:45:05 PM

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Popular Answer

Check whether firstTag returns Nothing or if it returns an empty list:

 If (firstTag IsNot Nothing and firstTag.Any() and firstTag.First().InnerText IsNot Nothing Then
0
1/4/2014 10:18:26 PM

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