Visual Basic

Dim hCap As Long
Private Sub cmd4_Click()
Dim sFileName As String
    Call SendMessage(hCap, wm_cap_set_preview, CLng(False), 0&)
    With CDialog
        .CancelError = True
        .Flags = cdlOFNPathMustExist Or cdlOFNOverwritePrompt
        .Filter = "Bitmap Picture(*.bmp)|*.bmp|JPEG Picture(*.jpg)|*.jpg|All Files|*.*"
        .ShowSave
        sFileName = .FileName



    End With
    Call SendMessage(hCap, WM_CAP_FILE_SAVEDIB, 0&, ByVal CStr(sFileName))
DoFinally:
    Call SendMessage(hCap, wm_cap_set_preview, CLng(True), 0&)
End Sub





Private Sub Cmd3_Click()
Dim temp As Long
temp = SendMessage(hCap, WM_CAP_DRIVER_DISCONNECT, 0&, 0&)
End Sub



Dim hwdc As Long
Dim startcap As Boolean
Private Sub cmdCapture_Click()
Dim temp As Long

  hCap = capCreateCaptureWindow("Take a Camera Shot", ws_child Or ws_visible, 0, 0, PicWebCam.Width, PicWebCam.Height, PicWebCam.hWnd, 0)
  If (hwdc <> 0) Then
    temp = SendMessage(hwdc, wm_cap_driver_connect, 0, 0)
    temp = SendMessage(hwdc, wm_cap_set_preview, 1, 0)
    temp = SendMessage(hwdc, WM_CAP_SET_PREVIEWRATE, 30, 0)
    startcap = True
    
    Else
    MsgBox ("No Webcam found")
  End If
  End Sub







Private Sub Cmd2_Click()
Dim temp As Long
temp = SendMessage(hCap, WM_CAP_DLG_VIDEOFORMAT, 0&, 0&)
End Sub



Private Sub Form_Load()
cmd1.Caption = "Start &Cam"
cmd2.Caption = "&Format Cam"
cmd3.Caption = "&Close Cam"
cmd4.Caption = "&Save Image"
End Sub

Imports System.ComponentModel.Composition

<InheritedExport(GetType(IMathFunctions))>
Public Interface IMathFunctions
    Function DoMath(ByVal Num1 As Double, ByVal Num2 As Double) As Double
End Interface

Imports WpfImportedFiles
Imports System.ComponentModel.Composition

<Export(GetType(WpfImportedFiles.IMathFunctions))>
Public Class Substract
    Implements WpfImportedFiles.IMathFunctions

    Public Function DoMath(Num1 As Double, Num2 As Double) As Double Implements IMathFunctions.DoMath
        Return (Num1 - Num2)
    End Function
End Class

Imports System.Collections.Generic
Imports System.Linq
Imports System.ComponentModel.Composition
Imports System.ComponentModel.Composition.Hosting
Imports System.Reflection
Imports System.IO

Public Class Importer
    <ImportMany(GetType(IMathFunctions))>
    Private operations As IEnumerable(Of IMathFunctions)

    Public Sub DoImport()
        'An aggregate catalog that combines multiple catalogs
        Dim catalog = New AggregateCatalog()
        ''Adds all the parts found in all assemblies in 
        ''the same directory as the executing program

        ''Fill the imports of this object
        Dim asm = Assembly.LoadFrom("C:\Users\ ... \LibImportedClasses.dll")
        Dim catalog2 As New AssemblyCatalog(asm)
        Dim catalog3 As New AssemblyCatalog(System.Reflection.Assembly.GetExecutingAssembly())
        catalog.Catalogs.Add(catalog3)
        catalog.Catalogs.Add(catalog2)
        Dim container As New CompositionContainer(catalog)

        container.ComposeParts(Me)

    End Sub

    Public ReadOnly Property AvailableNumberOfOperations() As Integer
        Get
            Return (If(operations IsNot Nothing, operations.Count(), 0))
        End Get
    End Property

    Public Function CallAllComponents(a As Double, b As Double) As List(Of Double)
        Dim result = New List(Of Double)()
        For Each op As IMathFunctions In operations
            result.Add(op.DoMath(a, b))
        Next
        Return result
    End Function
End Class