using System;
using System.Windows.Forms;
using System.Runtime.InteropServices;
namespace CaptionTimetableSupporet
{
public partial class MainForm : Form
{
// P/Invoke constants
private const int WM_SYSCOMMAND = 0x112;
private const int MF_STRING = 0x0;
private const int MF_SEPARATOR = 0x800;
// P/Invoke declarations
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern IntPtr GetSystemMenu(IntPtr hWnd, bool bRevert);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern bool AppendMenu(IntPtr hMenu, int uFlags, int uIDNewItem, string lpNewItem);
[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
private static extern bool InsertMenu(IntPtr hMenu, int uPosition, int uFlags, int uIDNewItem, string lpNewItem);
// ID for the About item on the system menu
private int SYSMENU_ABOUT_ID = 0x1;
protected override void OnHandleCreated(EventArgs e)
{
base.OnHandleCreated(e);
// Get a handle to a copy of this form's system (window) menu
IntPtr hSysMenu = GetSystemMenu(this.Handle, false);
// Add a separator
AppendMenu(hSysMenu, MF_SEPARATOR, 0, string.Empty);
// Add the About menu item
AppendMenu(hSysMenu, MF_STRING, SYSMENU_ABOUT_ID, "&About…");
}
protected override void WndProc(ref Message m)
{
base.WndProc(ref m);
// Test if the About item was selected from the system menu
if ((m.Msg == WM_SYSCOMMAND) && ((int)m.WParam == SYSMENU_ABOUT_ID))
{
MessageBox.Show("Custom About Dialog");
}
}
}
}