Breadcrumbs

[Skillful]

In this tutorial I will show you how to extract text out of webpage sources in order to use them in your program..

For example: http://www.bbc.co.uk/radio1/chart/singles

We want to extract the top 40 singles from this online chart.

First we will put the source code of the page in a string:

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Dim Source as String = New System.Net.WebClient().DownloadString("http://www.bbc.co.uk/radio1/chart/singles") 

Note that some websites may return an error and realize that you are not an actual visitor, in that case we will need a webrequest..

Now that we have the source code of the page in a string.. we just need to use regex/getbetween/split to extract the strings we want to get..

Ctrl+U on the site in your browser and find where the text you want to get is, that will be your Regex..

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Dim Regex As String = "  <img src=""/radio1/images/auto/70x70/.*"" alt=""(.+)?"" class=""cover"" height=""70"" width=""70"" />" 

I just use .* as a wildcard which could be anything and put (.+)? where ever the text will be that I need to get, which will be M.Groups(1).Value

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For Each M As System.Text.RegularExpressions.Match In System.Text.RegularExpressions.Regex.Matches(Source, Regex)
           MessageBox.Show(M.Groups(1).Value)
        Next 

Theres your loop and there you have it.

Regards,
Skillful

[MrAksel]

You might want to tell more about Regular Expressions, since this does only work on one webpage and people to don't know how to use regex won't be able to use this to get other information.

[Skillful]

Yeah this is true.
Just wrote this while on my dad's laptop.
Will update it later

[CdnReaper]

how can i do the same thing but have it posted to a label instead of a messagebox