Opening files with VB.NET program

Question

I recently learned how to use VB.NET to set your program as the default for a chosen extension. You would write code to set a registry value. The problem is, when you open t

Answer 1

The path to the file is passed to your program as a command line parameter. Your program will need to read the command line parameters and react accordingly.

Here is some example code demonstrating how to read the command line parameters:

  Sub Main()
    Dim s() As String = System.Environment.GetCommandLineArgs()
    ' write code to open the file here...
    Console.WriteLine(s(1))
  End Sub

To help with debugging this you can specify command-line arguments in the Visual Studio IDE:

1. With a project selected in Solution Explorer, on the Project menu, click Properties.
2. Click the Debug tab.
3. In the Command line arguments field, enter the command-line arguments you wish to use.

Answer 2

You can also declare your Sub Main to receive the command line arguments:

Sub Main(Args() As String)

End Sub

Answer 3

The filename is passed to your program by the OS

Sub Main()
    Dim s() As String = System.Environment.GetCommandLineArgs()
EndSub

MSDN docs