File Association in VB.NET

Public Class Form1
       Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        associateFile("HELLO", ".hello", "C:\myicon.ico", "My Hello File", Application.ExecutablePath)
    End Sub

Public Sub associateFile(ByVal mainKey As String, ByVal ext As String, ByVal iconPath As String, ByVal fileDescription As String, ByVal appPath As String)
        My.Computer.Registry.ClassesRoot.CreateSubKey(ext).SetValue("", mainKey, Microsoft.Win32.RegistryValueKind.String)
        My.Computer.Registry.ClassesRoot.CreateSubKey(mainKey).SetValue("", fileDescription, Microsoft.Win32.RegistryValueKind.String)
        My.Computer.Registry.ClassesRoot.CreateSubKey(mainKey & "\shell\open\command").SetValue("", appPath & " ""%l"" ", Microsoft.Win32.RegistryValueKind.String)
        My.Computer.Registry.ClassesRoot.CreateSubKey(mainKey & "\DefaultIcon").SetValue("", iconPath, Microsoft.Win32.RegistryValueKind.ExpandString)
    End Sub

    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        MsgBox("Hello, " & My.Computer.FileSystem.ReadAllText(My.Application.CommandLineArgs(0)) & " World!")
    End Sub
    End Class

Private Sub Association_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Association.Click
    Dim rslt As MsgBoxResult
    rslt = MsgBox("Are you sure you want .txt and .rtf files to open with this application?", MsgBoxStyle.YesNo, "Change File Association?")

    If rslt = MsgBoxResult.Yes Then
        AssociateExtFile()
    ElseIf rslt = MsgBoxResult.No Then
        Exit Sub
    End If
End Sub

Private Sub AssociateExtFile()

    Try

        Dim extension As String = ".txt"
        Dim name As String = "textFile"
        Dim description As String = "text Formats File"
        Dim applicationPath As String = Environment.GetCommandLineArgs()(0)
        Dim iconPath As String = Path.Combine(Path.GetDirectoryName(applicationPath), "JWA.ico")

        AssociateFile(extension, name, description, iconPath, applicationPath)

    Catch ex As Exception
        MsgBox("Unable to associate file type" & ex.ToString)
    End Try
End Sub


Private Shared Sub AssociateFile(ByVal extension As String, ByVal name As String, ByVal description As String, ByVal iconPath As String, ByVal applicationPath As String)

    'Validate arguments
    If String.IsNullOrEmpty(extension) OrElse Not extension.StartsWith(".") Then Throw New ArgumentException("Extension must not be null, must also start with '.'", "extension")
    If String.IsNullOrEmpty(description) Then Throw New ArgumentException("description must not be null", "description")

    'Allow nothing to be passed for the icon file
    Dim iconFile As FileInfo = Nothing
    If iconPath IsNot Nothing Then
        iconFile = New FileInfo(iconPath)
        If Not iconFile.Exists Then Throw New ArgumentException("Icon file does not exist", "iconPath")
    End If

    Dim applicationFile As New FileInfo(applicationPath)
    If Not applicationFile.Exists Then Throw New ArgumentException("Application file does not exist", "applicationFile")

    'Create .extension value
    My.Computer.Registry.ClassesRoot.CreateSubKey(extension).SetValue("", name, Microsoft.Win32.RegistryValueKind.String)

    'Create filename value
    My.Computer.Registry.ClassesRoot.CreateSubKey((name & "\shell\open\command")).SetValue("", (applicationFile.FullName & " ""%l"" "), Microsoft.Win32.RegistryValueKind.String)

    'Set the description for the file name
    My.Computer.Registry.ClassesRoot.CreateSubKey(name).SetValue("", description)

    'Associate an icon if we were passed one
    If iconFile IsNot Nothing Then _
        My.Computer.Registry.ClassesRoot.CreateSubKey((name & "\DefaultIcon")).SetValue("", iconFile.FullName, Microsoft.Win32.RegistryValueKind.String)

End Sub