.NET Shell Extensions - Shell Drop Handlers

using System;
using System.Runtime.InteropServices;

namespace SharpShell.Interop
{
    internal delegate bool  AddPropertySheetPageDelegate(IntPtr hPropSheetPage, IntPtr lParam);

    /// <summary>
    /// IShellPropSheetExt
    /// </summary>
    [ComImport]
    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    [Guid("000214e9-0000-0000-c000-000000000046")]
    internal interface IShellPropSheetExt
    {
        [PreserveSig()]
        int AddPages(IntPtr pfnAddPage, IntPtr lParam);

        [PreserveSig()]
        int ReplacePage(uint uPageID, AddPropertySheetPageDelegate lpfnReplacePage, IntPtr lParam);
    }


    public delegate uint PropSheetCallback(IntPtr hwnd, uint uMsg, ref PROPSHEETPAGE ppsp);
	public delegate bool DialogProc(IntPtr hwndDlg, uint uMsg, IntPtr wParam, IntPtr lParam); 
    
    [Flags]
	public enum PSP : uint
	{
		DEFAULT				= 0x00000000,
		DLGINDIRECT			= 0x00000001,
		USEHICON			= 0x00000002,
		USEICONID			= 0x00000004,
		USETITLE			= 0x00000008,
		RTLREADING			= 0x00000010,

		HASHELP				= 0x00000020,
		USEREFPARENT		= 0x00000040,
		USECALLBACK			= 0x00000080,
		PREMATURE			= 0x00000400,

		HIDEHEADER			= 0x00000800,
		USEHEADERTITLE		= 0x00001000,
		USEHEADERSUBTITLE	= 0x00002000
	}
}