I am trying to create a program that renames files to 1 - (however many files are in the folder) and also convert .pngs to .bmps, I had done this but I messed it up a little. I am not that experienced with VB.Net but I am looking to learn so any help would be great. I have tried this myself but as you can see in the code I've gone the wrong way about it. I'm clueless now to how to do this, any help would be appreciated 
VB.NET:
Dim fileNo As Integer
If RadioButton1.Checked = True Then
Dim files As String()
files = IO.Directory.GetFiles(TextBox1.Text)
Dim filepath_new As String
filepath_new = TextBox1.Text
For Each filepath As String In files
For x = 0 To fileNo
My.Computer.FileSystem.RenameFile("*", x & ".bmp")
System.IO.File.Move(filepath, filepath_new)
x = x + 1
Next x
Next