IsDialogMessage function

Determines whether a message is intended for the specified dialog box and, if it is, processes the message.

Syntax

BOOL WINAPI IsDialogMessage(
  _In_ HWND  hDlg,
  _In_ LPMSG lpMsg
);

Parameters

hDlg [in]

Type: HWND

A handle to the dialog box.

lpMsg [in]

Type: LPMSG

A pointer to an MSG structure that contains the message to be checked.

Return value

Type: BOOL

If the message has been processed, the return value is nonzero.

If the message has not been processed, the return value is zero.

Remarks

Although the IsDialogMessage function is intended for modeless dialog boxes, you can use it with any window that contains controls, enabling the windows to provide the same keyboard selection as is used in a dialog box.

When IsDialogMessage processes a message, it checks for keyboard messages and converts them into selections for the corresponding dialog box. For example, the TAB key, when pressed, selects the next control or group of controls, and the DOWN ARROW key, when pressed, selects the next control in a group.

Because the IsDialogMessage function performs all necessary translating and dispatching of messages, a message processed by IsDialogMessage must not be passed to the TranslateMessage or DispatchMessage function.

IsDialogMessage sends WM_GETDLGCODE messages to the dialog box procedure to determine which keys should be processed.

IsDialogMessage can send DM_GETDEFID and DM_SETDEFID messages to the window. These messages are defined in the Winuser.h header file as WM_USER and WM_USER + 1, so conflicts are possible with application-defined messages having the same values.

Requirements

See also

Reference

DispatchMessage

DM_GETDEFID

DM_SETDEFID

MSG

TranslateMessage

WM_GETDLGCODE

WM_USER

Conceptual

Dialog Boxes