Thread: DLL Error with VB .NET Program

Ok, so i was looking around on google about how to incorporate DLL's written in C with VB .NET GUI's because its stupidly simple to create one in VB and C is faster. So I want to learn how to mix the two and i found a page of an example thats supposed to do just this (here: http://www.codeproject.com/Purgatory/c_dll_in_vb.asp ). But when I execute the code, I always get this error:

An unhandled exception of type 'System.EntryPointNotFoundException' occurred in Call_C_dll.exe

Additional information: Unable to find an entry point named ReturnInParam in DLL vcdll.dll.

VB Code:

Code:

Public Class Form1
    Inherits System.Windows.Forms.Form
 _
| Windows Form Designer Generated Code |
 -

    <DllImport("vcdll.dll", CallingConvention:=CallingConvention.Cdecl)> _
    Private Shared Sub ReturnInParam(ByRef Stan As Integer, _
        ByRef Message As String)
    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        Dim Num As Integer = 8
        Dim Message As String = "Hey"
        ReturnInParam(Num, Message)
        MessageBox.Show(Message)
    End Sub
End Class

C Code:

Code:

#include <WINDOWS.H>


      LPCSTR DisplayStringByVal(LPCSTR pszString)
      {
          return "How's it goin? ";
      }

      
      void ReturnInParam(int* pnStan, char** pMsg)
      {
           long *buffer;
           char text[7] = "Hallo ";
           char name[sizeof(*pMsg)];
           
           strcpy(name, *pMsg);
           *pnStan = *pnStan + 5;
           
           buffer = (long *)calloc(sizeof(text)+sizeof(*pMsg), sizeof( char ) );
           *pMsg = (char *)buffer;
           
           // do not free the buffer, because it will be used by the caller
           //   free( buffer );
           strcpy(*pMsg, text);
           strcat(*pMsg, name);
      }

the name and path of the dll is correct so whats wrong? thanks