如何把其他Win32程序的窗体嵌入到我们托管的WinForm中

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Threading;

namespace TestParentChildForm
{
    public partial class Form1 : Form
    {
        [DllImport("user32.dll")]
        private static extern int SetParent(IntPtr hWndChild, IntPtr hWndParent);

        [DllImport("user32.dll")]
        private static extern bool ShowWindowAsync(IntPtr hWnd, int nCmdShow);

        [DllImport("user32.dll", SetLastError = true)]
        private static extern bool PostMessage(IntPtr hWnd, uint Msg, int wParam, int lParam);

        [DllImport("user32.dll", EntryPoint = "SetWindowPos")]
        private static extern bool SetWindowPos(IntPtr hWnd, int hWndInsertAfter,
                    int X, int Y, int cx, int cy, uint uFlags);

        [DllImport("user32.dll")]
        private static extern int SendMessage(IntPtr hWnd, uint Msg, int wParam, int lParam);

        [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        private static extern uint SetWindowLong(IntPtr hwnd, int nIndex, uint newLong);

        [DllImport("user32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        private static extern uint GetWindowLong(IntPtr hwnd, int nIndex);

        [DllImport("user32.dll", CharSet = CharSet.Auto)]
        private static extern bool ShowWindow(IntPtr hWnd, short State);

        private const int HWND_TOP = 0x0;
        private const int WM_COMMAND = 0x0112;
        private const int WM_QT_PAINT = 0xC2DC;
        private const int WM_PAINT = 0x000F;
        private const int WM_SIZE = 0x0005;
        private const int SWP_FRAMECHANGED = 0x0020;
        private enum ShowWindowStyles : short
        {
            SW_HIDE = 0,
            SW_SHOWNORMAL = 1,
            SW_NORMAL = 1,
            SW_SHOWMINIMIZED = 2,
            SW_SHOWMAXIMIZED = 3,
            SW_MAXIMIZE = 3,
            SW_SHOWNOACTIVATE = 4,
            SW_SHOW = 5,
            SW_MINIMIZE = 6,
            SW_SHOWMINNOACTIVE = 7,
            SW_SHOWNA = 8,
            SW_RESTORE = 9,
            SW_SHOWDEFAULT = 10,
            SW_FORCEMINIMIZE = 11,
            SW_MAX = 11
        }
        private Process p = null;

        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            p = new Process();
            //需要启动的程序
            p.StartInfo.FileName = textBox1.Text;
            //为了美观,启动的时候最小化程序
            p.StartInfo.WindowStyle = ProcessWindowStyle.Minimized;
            //启动
            p.Start();

            //这里必须等待,否则启动程序的句柄还没有创建,不能控制程序
            Thread.Sleep(1000);
            //最大化启动的程序
            ShowWindow(p.MainWindowHandle, (short)ShowWindowStyles.SW_NORMAL);
            //设置被绑架程序的父窗口
            SetParent(p.MainWindowHandle, this.panel1.Handle);
            //改变尺寸
            ResizeControl();
        }

        //控制嵌入程序的位置和尺寸
        private void ResizeControl()
        {
            SendMessage(p.MainWindowHandle, WM_COMMAND, WM_PAINT, 0);
            PostMessage(p.MainWindowHandle, WM_QT_PAINT, 0, 0);
            SetWindowPos(p.MainWindowHandle, HWND_TOP, 0 - 5, 0 - 41, panel1.Width, panel1.Height + 36,SWP_FRAMECHANGED);
            SendMessage(p.MainWindowHandle, WM_COMMAND, WM_SIZE, 0);
        }

        private void Form1_SizeChanged(object sender, EventArgs e)
        {
            ResizeControl();
        }
    }
}