EnumWindows function (winuser.h)

Enumerates all top-level windows on the screen by passing the handle to each window, in turn, to an application-defined callback function. EnumWindows continues until the last top-level window is enumerated or the callback function returns FALSE.

Syntax

BOOL EnumWindows(
  [in] WNDENUMPROC lpEnumFunc,
  [in] LPARAM      lParam
);

Parameters

[in] lpEnumFunc

Type: WNDENUMPROC

A pointer to an application-defined callback function. For more information, see EnumWindowsProc.

[in] lParam

Type: LPARAM

An application-defined value to be passed to the callback function.

Return value

Type: BOOL

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

If EnumWindowsProc returns zero, the return value is also zero. In this case, the callback function should call SetLastError to obtain a meaningful error code to be returned to the caller of EnumWindows.

Remarks

The EnumWindows function does not enumerate child windows, with the exception of a few top-level windows owned by the system that have the WS_CHILD style.

This function is more reliable than calling the GetWindow function in a loop. An application that calls GetWindow to perform this task risks being caught in an infinite loop or referencing a handle to a window that has been destroyed.

Note  For Windows 8 and later, EnumWindows enumerates only top-level windows of desktop apps.
 

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header winuser.h (include Windows.h)
Library User32.lib
DLL User32.dll
API set ext-ms-win-ntuser-window-l1-1-0 (introduced in Windows 8)

See also

Conceptual

EnumChildWindows

EnumWindowsProc

GetWindow

Reference

Windows