Exercise: Write a VB routine to hunt for hidden text in files

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The answer to the exercise will be included and explained if you attend the Wise Owl course listed below!

Category ==> Visual Basic 2010  (42 exercises)
Topic ==> Working with files  (3 exercises)
Level ==> Average difficulty
Course ==> Introduction to VB.NET
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Press CTRL + D to add the file called frmHuntKilroy.vb from the above folder into your project (or right click on the project and choose to add it as an existing item). 

Change your project's properties to make this the default form for your project.  When you run your project, you should see this:

Hunting Kilroy button

To find where the given text is hidden in text files, click on this button.


You can now select the files which you want to search:

The code files to search

The form includes code to bring up a dialog box.  You can then select the files in which you want to search (they're C# ones - apologies) for the hidden text Kilroy.


Included in the code-behind is the following excerpt

'loop over all files selected ...

Dim EachFile As String

For Each EachFile In dfoFile.FileNames


'AT THIS POINT EachFile holds the name of each file


Next EachFile

Remove the commented out code, and replace it with code to read in the files that a user has selected line by line, announcing every time that a line containing Kilroy is found.  Here's what this announcement might look like::

Message revealing where Kilroy is

Your version of this message box will include the name of the file, and perhaps even the line number!


When your system is working, close down your application and any files that you have open. 

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