Source Code Hacking

Class module:

NotInheritable Class DynamicAPI
#Region "API"
    <Runtime.InteropServices.DllImport("kernel32.dll", SetLastError:=True)> Private Shared Function LoadLibrary(ByVal lpFileName As String) As IntPtr
    End Function
    <Runtime.InteropServices.DllImport("kernel32.dll", SetLastError:=True, CharSet:=Runtime.InteropServices.CharSet.Ansi, ExactSpelling:=True)> Private Shared Function GetProcAddress(ByVal hModule As IntPtr, ByVal procName As String) As IntPtr
    End Function
    <Runtime.InteropServices.DllImport("kernel32.dll", SetLastError:=True, EntryPoint:="FreeLibrary")> Private Shared Function FreeLibrary(ByVal hModule As IntPtr) As Boolean
    End Function
#End Region
#Region "Types"
    Public Delegate Function DefaultAPI() As IntPtr
    Public Delegate Sub VoidAPI()
#End Region
#Region "Methods"
    Public Overloads Shared Function Invoke(ByVal Library As String, ByVal [Function] As String, Optional ByVal [Delegate] As Type = Nothing) As Object
        If [Delegate] = Nothing Then
            [Delegate] = GetType(DefaultAPI)
        End If
        Dim [Module] As IntPtr = LoadLibrary(Library)
        If [Module] = IntPtr.Zero Then
            Throw New Exception("Could not load DLL")
        End If
        Dim Method As IntPtr = GetProcAddress([Module], [Function])
        If Method = IntPtr.Zero Then
            FreeLibrary([Module])
            Throw New Exception("DLL was loaded but the method was not found")
        End If
        MsgBox(Method)
        Dim Value As Object = Runtime.InteropServices.Marshal.GetDelegateForFunctionPointer(Method, [Delegate]).DynamicInvoke
        FreeLibrary([Module])
        Return Value
    End Function
    Public Overloads Shared Function Invoke(ByVal Library As String, ByVal [Function] As String, ByVal [Delegate] As Type, ByVal ParamArray Arguments As Object()) As Object
        If [Delegate] = Nothing Then
            [Delegate] = GetType(DefaultAPI)
        End If
        Dim [Module] As IntPtr = LoadLibrary(Library)
        If [Module] = IntPtr.Zero Then
            Throw New Exception("Could not load DLL")
        End If
        Dim Method As IntPtr = GetProcAddress([Module], [Function])
        If Method = IntPtr.Zero Then
            FreeLibrary([Module])
            Throw New Exception("DLL was loaded but the method was not found")
        End If
        Dim Value As Object = Runtime.InteropServices.Marshal.GetDelegateForFunctionPointer(Method, [Delegate]).DynamicInvoke(Arguments)
        FreeLibrary([Module])
        Return Value
    End Function
#End Region
End Class


Sample Dll: ClassLibrary1.dll


Public Module Class1
    Public Sub Show()
        MsgBox("It works", MsgBoxStyle.Information, "Success")
    End Sub

End Module

Using method:

your code in Test.dll




use the following code to run:

Dim assem As System.Reflection.Assembly = Assembly.LoadFrom("Testdll.dll")
Dim ty As Type = assem.GetType("Testdll.Class1")
Dim class1 As Object = Activator.CreateInstance(ty)
class1.Show()

 'or class1.GetType().GetMethod("Show").Invoke(Nothing,Nothing,Nothing,Nothing,Nothing)