VS 2005 Deleting Files From A Folder?

I have created a project where I can attach files and I am displaying the name of the file, example:

Mytestfile.doc
mytestfile.txt
Mytestfile.pdf

I have the names being displayed on a listbox, so far everything is working just the way I expected to work.When a file is selected from my opendialogbox, the file gets saved into a folder under my local disk, so far so good.The problem that I am having is deleting the file from the folder.I have added a delete button and I would like to when I click or highlight one of the file names to go into where the file was saved previously and deleted This is the code that I have for the delete funtion:

[CODE Dim sFileName As String = "C:program filesSupport DeskAttachments" & ListBox1.Text
System.IO.File.Delete(sFileName)][/code]

The problem is that if I add the code to the clcik event under the listbox, it works great, but if I add the code to the click event under my delete button, it doesn't work, what I found is that under the path, if I am under the click event from the listbox when it gets to the lisxtbox.text it displays the file name, which is what I whant, but when i tried the code under the click event under my delete button the listbox.text is blank.