Microsoft Windows CE 3.0  

CeGetWindowLong (RAPI)

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This function retrieves information about the specified window. CeGetWindowLongalso retrieves the 32-bit (long) value at the specified offset into the extra window memory of a window.

CeGetWindowLongis a remote application interface (RAPI), which enables an application running on a desktop computer to make function calls on a Windows CE–based device.

LONG
CeGetWindowLong(
HWND
hWnd
,
int
nIndex
);

Parameters

hWnd
Handle to the window and, indirectly, the class to which the window belongs.
nIndex
Specifies the zero-based offset to the value to be retrieved. Valid values are in the range zero through the number of bytes of extra window memory, minus four; for example, if you specified 12 or more bytes of extra memory, a value of 8 would be an index to the third 32-bit integer. To retrieve any other value, specify one of the following values:
Value Description
GWL_EXSTYLE Retrieves the extended window styles.
GWL_STYLE Retrieves the window styles.
GWL_WNDPROC Retrieves the address of the window procedure, or a handle representing the address of the window procedure. You must use the CallWindowProcfunction to call the window procedure.
GWL_ID Not supported.
GWL_USERDATA Retrieves the 32-bit value associated with the window. Each window has a corresponding 32-bit value intended for use by the application that created the window. Windows CE versions 2.0 and later support this value, but Windows CE versions 1.0 and 1.01 do not.

The following values are also available when the hWndparameter identifies a dialog box:

Value Description
DWL_MSGRESULT Retrieves the return value of a message processed in the dialog box procedure.
DWL_USER Retrieves extra information private to the application, such as handles or pointers.

Return Values

The requested 32-bit value indicates success. Zero indicates failure. To get extended error information, call CeGetLastError.

Remarks

The nIndexparameter must be a multiple of 4 bytes.

Unaligned access is not supported.

When working with RAPI for Windows CE versions 1.0 and 1.01, use the PegGetWindowLongfunction. This function does not support the DWL_DLGPROC value in the nIndexparameter.

Requirements

Runs On Versions Defined in Include Link to
Windows CE OS 2.0 and later Rapi.h    

See Also

CallWindowProc, CeGetLastError, RegisterClass, SetParent, SetWindowLong, WNDCLASS