[VB.NET] استفسار :- بخصوص اخذ نص من برنامج اخر WM_GETTEXT

كود :
Imports System.Runtime.InteropServices

Public Class Form1

    Private Const WM_GETTEXT As Integer = &HD

    Declare Auto Function SendMessage Lib "user32.dll" (ByVal hWnd As IntPtr, ByVal msg As Integer,

    ByVal wParam As IntPtr, ByVal lParam As IntPtr) As IntPtr

    <DllImport("user32.dll", SetLastError:=True, CharSet:=CharSet.Auto)>

    Private Shared Function FindWindowEx(ByVal parentHandle As IntPtr,

                                         ByVal childAfter As IntPtr,

                                         ByVal lclassName As String,

                                         ByVal windowTitle As String) As IntPtr

    End Function



    Declare Auto Function FindWindow Lib "user32.dll" (ByVal lpClassName As String, ByVal lpWindowName As String) As IntPtr



    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        'Find the running notepad window

        Dim Hwnd As IntPtr = FindWindow(Nothing, "uuu.txt - Notepad")



        'Alloc memory for the buffer that recieves the text

        Dim Handle As IntPtr = Marshal.AllocHGlobal(100)



        'send WM_GWTTEXT message to the notepad window

        Dim NumText As Integer = SendMessage(Hwnd, WM_GETTEXT, 50, Handle)



        'copy the characters from the unmanaged memory to a managed string

        Dim Text As String = Marshal.PtrToStringUni(Handle)



        'Display the string using a label

        Label1.Text = Text



        'Find the Edit control of the Running Notepad

        Dim ChildHandle As IntPtr = FindWindowEx(Hwnd, IntPtr.Zero, "Edit", Nothing)



        'Alloc memory for the buffer that recieves the text

        Dim Hndl As IntPtr = Marshal.AllocHGlobal(200)



        'Send The WM_GETTEXT Message

        NumText = SendMessage(ChildHandle, WM_GETTEXT, 200, Hndl)



        'copy the characters from the unmanaged memory to a managed string

        Text = Marshal.PtrToStringUni(Hndl)



        'Display the string using a label

        Label2.Text = Text



    End Sub



End Class