SetWindowTextA function (winuser.h)

Changes the text of the specified window's title bar (if it has one). If the specified window is a control, the text of the control is changed. However, SetWindowText cannot change the text of a control in another application.


BOOL SetWindowTextA(
  [in]           HWND   hWnd,
  [in, optional] LPCSTR lpString


[in] hWnd

Type: HWND

A handle to the window or control whose text is to be changed.

[in, optional] lpString


The new title or control text.

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 the target window is owned by the current process, SetWindowText causes a WM_SETTEXT message to be sent to the specified window or control. If the control is a list box control created with the WS_CAPTION style, however, SetWindowText sets the text for the control, not for the list box entries.

To set the text of a control in another process, send the WM_SETTEXT message directly instead of calling SetWindowText.

The SetWindowText function does not expand tab characters (ASCII code 0x09). Tab characters are displayed as vertical bar (|) characters.


For an example, see Sending a Message.


The winuser.h header defines SetWindowText as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.


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-l1-1-3 (introduced in Windows 10, version 10.0.10240)

See also