Linking vb.net GUI to c++ DLL functions

my apologies, i read your question wrong. i gave you the answer for something else, yes to use dlls in vb.net is the same as vb6, here is an example for using API calls too Private Declare Function FindWindow Lib "user32.dll" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Integer Private Declare Function PostMessage Lib "user32.dll" Alias "PostMessageA" (ByVal hwnd As Integer, ByVal wMsg As Integer, ByVal wParam As String, ByVal lParam As String) As Integer Private Const WM_CLOSE As Integer = &H10 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim frmTypes() As Type = Reflection.Assembly.GetExecutingAssembly.GetTypes Dim fType As Type Dim hwnd As Integer Try For Each fType In frmTypes If Not fType.Name = Me.Name Then '/// make sure we dont accidently close the main Form. hwnd = FindWindow(vbNullString, fType.Name) If Not hwnd = 0 Then PostMessage(hwnd, WM_CLOSE, vbNullString, vbNullString) End If End If Next Catch ex As Exception MessageBox.Show(ex.Message) Finally MyBase.Close() '/// now all other Form's are closed , we can close the main Form. End Try End Sub

hi.. Thanks for your advice. i have to access the c++'s dll functions through the vb.net . But have no idea to do it.. Is it the same the same method as in vb 6.0? such as below? which declared the functions of dll? thanks.. Declare Function ArrayExample Lib "../testdll_library.dll" (ByRef Data() As String, ByVal Index As Integer) As String Declare Sub CallbackExample Lib "../testdll_library.dll" (ByVal Addr1 As Long)

are you talking about unmanaged c++ or managed? for managed c++ linking do the following create a vb.net project (dll) add your gui to this dll in your managed c++ project, make a reference to the vb dll (or project) and you can instantiate vb.net objects (gui) in your managed c++