C# does Shell, Part 4

using System;
using System.Runtime.InteropServices;

namespace ShellLib
{
	[ComImport]
	[InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
	[Guid("00BB2762-6A77-11D0-A535-00C04FD7D062")]
	public interface IAutoComplete 
	{
		/// <summary>
		/// Initializes the autocomplete object.
		/// </summary>
		[PreserveSig]
		Int32 Init(
			IntPtr hwndEdit,						// Handle to the window for the system edit control that is to 
													// have autocompletion enabled. 
			[MarshalAs(UnmanagedType.IUnknown)]
			Object punkACL,							// Pointer to the IUnknown interface of the string list object that 
													// is responsible for generating candidates for the completed 
													// string. The object must expose an IEnumString interface. 
			//IntPtr pwszRegKeyPath,
			[MarshalAs(UnmanagedType.LPWStr)]
			String pwszRegKeyPath,					// Pointer to an optional null-terminated Unicode string that gives
													// the registry path, including the value name, where the format 
													// string is stored as a REG_SZ value. The autocomplete object 
													// first looks for the path under HKEY_CURRENT_USER . If it fails,
													// it then tries HKEY_LOCAL_MACHINE . For a discussion of the 
													// format string, see the definition of pwszQuickComplete. 
			//IntPtr pwszQuickComplete);
			[MarshalAs(UnmanagedType.LPWStr)]
			String pwszQuickComplete);				// Pointer to an optional string that specifies the format to be
													// used if the user enters some text and presses CTRL+ENTER. Set
													// this parameter to NULL to disable quick completion. Otherwise, 
													// the autocomplete object treats pwszQuickComplete as a sprintf 
													// format string, and the text in the edit box as its associated 
													// argument, to produce a new string. For example, set 
													// pwszQuickComplete to "http://www. %s.com/". When a user enters
													// "MyURL" into the edit box and presses CTRL+ENTER, the text in 
													// the edit box is updated to "http://www.MyURL.com/". 

		/// <summary>
		/// Enables or disables autocompletion.
		/// </summary>
		[PreserveSig]
		Int32 Enable(
			Int32 fEnable);							// Value that is set to TRUE to enable autocompletion, or to 
													// FALSE to disable it. 
				
	}
}