MDI Form

Public Class Form1
    Inherits System.Windows.Forms.Form
    Declare Function ShowWindow Lib "user32" (ByVal hWnd As System.IntPtr, ByVal nCmdShow As Integer) As Boolean
    Private Const SW_MINIMIZE As Integer = 6
    Private Const SW_MAXIMIZE As Integer = 3      'By Ahmed Salah =D
    Private Const SW_RESTORE As Integer = 9

    Declare Function SetParent Lib "user32" (ByVal hWndChild As System.IntPtr, ByVal hWndNewParent As System.IntPtr) As System.IntPtr

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim p As Process = System.Diagnostics.Process.Start("C:\Windows\notepad.exe")  'By Ahmed Salah =D
        p.WaitForInputIdle()
        SetParent(p.MainWindowHandle, Me.Handle)  'By Ahmed Salah =D
        ShowWindow(p.MainWindowHandle, SW_MAXIMIZE)
    End Sub
End Class