Binaryworld - List all COM components on local machine ... [ VB.net -> Windows ]

The following routine parses the registry and lists all the installed COM components:

' this code assumes that you have used this Imports statement
' Imports Microsoft.Win32

' Print ProgID, CLSID, and path of all the COM components
' installed on this computer.
Sub DisplayCOMComponents()
  ' Open the HKEY_CLASSES_ROOT\CLSID key
  Dim regClsid As RegistryKey = Registry.ClassesRoot.OpenSubKey("CLSID")

  ' Iterate over all the subkeys.
  Dim clsid As String
  For Each clsid In regClsid.GetSubKeyNames
    ' Open the subkey.
    Dim regClsidKey As RegistryKey = regClsid.OpenSubKey(clsid)

    ' Get the ProgID. (This is the default value for this key.)
    Dim ProgID As String = CStr(regClsidKey.GetValue(""))
    ' Get the InProcServer32 key, which holds the DLL path.
    Dim regPath As RegistryKey = regClsidKey.OpenSubKey("InprocServer32")
    If regPath Is Nothing Then
      ' If not found, it isn't an in-process DLL server,
      ' let's see if it's an out-of-process EXE server.
      regPath = regClsidKey.OpenSubKey("LocalServer32")
    End If
    If Not (regPath Is Nothing) Then
      ' If either key has been found, retrieve its default value.
      Dim filePath As String = CStr(regPath.GetValue(""))
      ' Display all the relevant info gathered so far.
      Console.WriteLine(ProgId & " " & clsid & " -> " & filePath)
      ' Always close registry keys.
      regPath.Close()
    End If
    ' Always close registry keys.
    regClsidKey.Close()
  Next
End Sub