.NET Shell Extensions - Shell Preview Handlers

using System.Runtime.InteropServices;

namespace SharpShell.Interop
{
    /// <summary>
    /// Enables preview handlers to pass keyboard shortcuts to the host. This interface retrieves a list of keyboard shortcuts and directs the host to handle a keyboard shortcut.
    /// </summary>
    [ComImport]
    [InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
    [Guid("fec87aaf-35f9-447a-adb7-20234491401a")]
    public interface IPreviewHandlerFrame
    {
        /// <summary>
        /// Gets a list of the keyboard shortcuts for the preview host.
        /// </summary>
        /// <param name="pinfo">A pointer to a PREVIEWHANDLERFRAMEINFO structure that receives accelerator table information.</param>
        /// <returns>If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.</returns>
        [PreserveSig]
        int GetWindowContext(PREVIEWHANDLERFRAMEINFO pinfo);

        /// <summary>
        /// Directs the host to handle an keyboard shortcut passed from the preview handler.
        /// </summary>
        /// <param name="pmsg">A pointer to a WM_COMMAND or WM_SYSCOMMAND window message that corresponds to a keyboard shortcut.</param>
        /// <returns>If the keyboard shortcut is one that the host intends to handle, the host will process it and return S_OK; otherwise, it returns S_FALSE.</returns>
        [PreserveSig]
        int TranslateAccelerator(MSG pmsg);
    };
}