IShellWindows::Register method (exdisp.h)

Registers an open window as a Shell window; the window is specified by handle.

Syntax

HRESULT Register(
  [in]  IDispatch *pid,
  [in]  long      hwnd,
  [in]  int       swClass,
  [out] long      *plCookie
);

[in] pid

The window's IDispatch interface.

[in] hwnd

Type: long

A handle that specifies the window to register.

[in] swClass

Type: int

A member of ShellWindowTypeConstants that specifies the type of window.

[out] plCookie

Type: long*

The window's cookie.

Type: HRESULT

If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.

In the context of the Shell windows collection, a cookie is a token that uniquely identifies a registered Shell window.

Use this method to register an open window; if the window is pending open, use IShellWindows::RegisterPending instead.