MSGBOXPARAMSA structure (winuser.h)

Contains information used to display a message box. The MessageBoxIndirect function uses this structure.

Syntax

typedef struct tagMSGBOXPARAMSA {
  UINT           cbSize;
  HWND           hwndOwner;
  HINSTANCE      hInstance;
  LPCSTR         lpszText;
  LPCSTR         lpszCaption;
  DWORD          dwStyle;
  LPCSTR         lpszIcon;
  DWORD_PTR      dwContextHelpId;
  MSGBOXCALLBACK lpfnMsgBoxCallback;
  DWORD          dwLanguageId;
} MSGBOXPARAMSA, *PMSGBOXPARAMSA, *LPMSGBOXPARAMSA;

Members

cbSize

Type: UINT

The structure size, in bytes.

hwndOwner

Type: HWND

A handle to the owner window. This member can be NULL.

hInstance

Type: HINSTANCE

A handle to the module that contains the icon resource identified by the lpszIcon member, and the string resource identified by the lpszText or lpszCaption member.

lpszText

Type: LPCTSTR

A null-terminated string, or the identifier of a string resource, that contains the message to be displayed.

lpszCaption

Type: LPCTSTR

A null-terminated string, or the identifier of a string resource, that contains the message box title. If this member is NULL, the default title Error is used.

dwStyle

Type: DWORD

The contents and behavior of the dialog box. This member can be a combination of flags described for the uType parameter of the MessageBoxEx function.

In addition, you can specify the MB_USERICON flag (0x00000080L) if you want the message box to display the icon specified by the lpszIcon member.

lpszIcon

Type: LPCTSTR

Identifies an icon resource. This parameter can be either a null-terminated string or an integer resource identifier passed to the MAKEINTRESOURCE macro.

To load one of the standard system-defined icons, set the hInstance member to NULL and set lpszIcon to one of the values listed with the LoadIcon function.

This member is ignored if the dwStyle member does not specify the MB_USERICON flag.

dwContextHelpId

Type: DWORD_PTR

Identifies a help context. If a help event occurs, this value is specified in the HELPINFO structure that the message box sends to the owner window or callback function.

lpfnMsgBoxCallback

Type: MSGBOXCALLBACK

A pointer to the callback function that processes help events for the message box. The callback function has the following form:

VOID CALLBACK MsgBoxCallback(LPHELPINFO lpHelpInfo);

If this member is NULL, then the message box sends WM_HELP messages to the owner window when help events occur.

dwLanguageId

Type: DWORD

The language in which to display the text contained in the predefined push buttons. This value must be in the form returned by the MAKELANGID macro.

For a list of supported language identifiers, see Language Identifiers. Note that each localized release of Windows typically contains resources only for a limited set of languages. Thus, for example, the U.S. version offers LANG_ENGLISH, the French version offers LANG_FRENCH, the German version offers LANG_GERMAN, and the Japanese version offers LANG_JAPANESE. Each version offers LANG_NEUTRAL. This limits the set of values that can be used with the dwLanguageId parameter. Before specifying a language identifier, you should enumerate the locales that are installed on a system.

Remarks

Note

The winuser.h header defines MSGBOXPARAMS as an alias that 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 is not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Requirements

Requirement Value
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Header winuser.h (include Windows.h)

See also

Conceptual

Dialog Boxes

HELPINFO

LoadIcon

MAKEINTRESOURCE

MAKELANGID

MessageBoxEx

MessageBoxIndirect

Other Resources

Reference

WM_HELP