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vb.netcomlate-bindingoption-strict

Using early binding on a COM object


I have this piece of code that works very well and gives me the path the user's start menu:

    Dim oShell As Object = CreateObject("Shell.Application")
    MsgBox(oShell.NameSpace(11).Self.Path)

This obviously uses late binding. Now say I want to do this in C#, or in VB.NET strict mode, neither of which support this kind of syntax with late binding.

Is this possible? How?

Thanks for you help!


Solution

  • If you want to solve this the COM way you have to figure out, which COM reference to add in your VB project.

    Open regedit and navigate to HKEY_CLASSES_ROOT\<class id>\CLSID, i.e.

    HKEY_CLASSES_ROOT\Shell.Application\CLSID
    

    and you will find the class id which uniquely identifies the COM component.

    Under HKEY_CLASSES_ROOT\CLSID you can now look up which file is behind the COM component:

    HKEY_CLASSES_ROOT\CLSID\{13709620-C279-11CE-A49E-444553540000}\InProcServer32
    

    shows the following value:

    %SystemRoot%\system32\SHELL32.dll
    

    Now go to Visual Studio, and add a reference to this file (on the Browse tab of the Add References dialog). If you open up the projects properties, you will actually see that the nice name of the COM component added is Microsoft Shell Controls and Automation.

    Once the reference is added you can use the Shell.Application object as follows:

    Option Strict On
    
    Module PrintStartMenuLocation
    
        Sub Main()
            Dim shell As New Shell32.Shell
            Dim folder As Shell32.Folder
            Dim folderItem As Shell32.FolderItem
            Dim startMenuPath As String
    
            folder = shell.NameSpace(Shell32.ShellSpecialFolderConstants.ssfSTARTMENU)
            folderItem = CType(folder.Items(0), Shell32.FolderItem)
            startMenuPath = folderItem.Path
    
            Console.WriteLine(startMenuPath)
        End Sub
    
    End Module
    

    A version in C# would look as follows:

    class Program
    {
        static void Main(string[] args)
        {
            Shell32.Shell shell = new Shell32.Shell();
            Shell32.Folder folder = shell.NameSpace(Shell32.ShellSpecialFolderConstants.ssfSTARTMENU);
            Shell32.FolderItem folderItem = folder.Items().Item(0) as Shell32.FolderItem;
            string startMenuPath = folderItem.Path;
    
            Console.WriteLine(startMenuPath);
        }
    }
    

    However, if you simply need to retrieve the location of the Start Menu folder you can do the same directly in .NET using

    Dim path As String = System.Environment.GetFolderPath(Environment.SpecialFolder.StartMenu)