IsWindow function (winuser.h)

Determines whether the specified window handle identifies an existing window.

Syntax

BOOL IsWindow(
  [in, optional] HWND hWnd
);

Parameters

[in, optional] hWnd

Type: HWND

A handle to the window to be tested.

Return value

Type: BOOL

If the window handle identifies an existing window, the return value is nonzero.

If the window handle does not identify an existing window, the return value is zero.

Remarks

A thread should not use IsWindow for a window that it did not create because the window could be destroyed after this function was called. Further, because window handles are recycled the handle could even point to a different window.

Examples

For an example, see Creating a Modeless Dialog Box.

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

IsWindowEnabled

IsWindowVisible

Reference

Windows