#include <windows.h>
/* include all of the prebuilt Windows librarys to the fun stuff like GUI */
/* the "main" will return a 1 or 0 depending on how the application terminates */
int APIENTRY WinMain(
HINSTANCE hInstance, /* Handle to the current instance */
HINSTANCE hPrevInstance, /* Handle to the previous instance */
LPSTR lpCmdLine, /* pointer to command line arguments */
int nCmdShow) /* show state of the window */
{
/* call the messagebox function, no "parent", text to include, title bar text, and ? */
MessageBox( NULL,"display text","Close by clicking X or OK", NULL);
/* MessageBox(0, lpCmdLine, "", 0); could be from the command line parameter */
return 0; /* the "main" function now returns a good result, 0 */
}
/* Here's some explanations
#include <windows.h>
int APIENTRY WinMain(HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int nCmdShow)
{ MessageBox(NULL, "\tHello World!", "My first windows app", NULL);
return 0;
}
int MessageBox(
HWND hWnd,
LPCTSTR lpText,
LPCTSTR lpCaption,
UINT uType
);
hWnd: [in] Handle to the owner window of the msgbox to be created. If NULL, the message box has no owner window.
lpText: [in] Pointer to a null-terminated string that contains display message. If the string consists of more
than one line, you can separate the lines using a carriage return and/or linefeed character between each line.
lpCaption: [in] Pointer to a null-terminated string that contains the dialog box title. If this parameter is
NULL, the default title is Error.
uType: [in] Specifies the contents and behavior of the dialog box. This parameter can be a combination of flags
from the following groups of flags. To indicate the buttons displayed in the message box, specify one of the
following values.
MB_ABORTRETRYIGNORE
The message box contains three push buttons: Abort, Retry, and Ignore.
MB_CANCELTRYCONTINUE
Microsoft Windows 2000/XP: The message box contains three push buttons: Cancel, Try Again, Continue.
Use this message box type instead of MB_ABORTRETRYIGNORE.
MB_HELP
Windows 95/98/Me, Windows NT 4.0 and later: Adds a Help button to the message box. When the user
clicks the Help button or presses F1, the system sends a WM_HELP message to the owner.
MB_OK
The message box contains one push button: OK. This is the default.
MB_OKCANCEL
The message box contains two push buttons: OK and Cancel.
MB_RETRYCANCEL
The message box contains two push buttons: Retry and Cancel.
MB_YESNO
The message box contains two push buttons: Yes and No.
MB_YESNOCANCEL
The message box contains three push buttons: Yes, No, and Cancel.
To display an icon in the message box, specify one of the following values.
MB_ICONEXCLAMATION
An exclamation-point icon appears in the message box.
MB_ICONWARNING
An exclamation-point icon appears in the message box.
MB_ICONINFORMATION
An icon consisting of a lowercase letter i in a circle appears in the message box.
MB_ICONASTERISK
An icon consisting of a lowercase letter i in a circle appears in the message box.
MB_ICONQUESTION
A question-mark icon appears in the message box. The question-mark message icon is no longer
recommended because it does not clearly represent a specific type of message and because the phrasing
of a message as a question could apply to any message type. In addition, users can confuse the message
symbol question mark with Help information. Therefore, do not use this question mark message symbol in
your message boxes. The system continues to support its inclusion only for backward compatibility.
MB_ICONSTOP
A stop-sign icon appears in the message box.
MB_ICONERROR
A stop-sign icon appears in the message box.
MB_ICONHAND
A stop-sign icon appears in the message box.
To indicate the default button, specify one of the following values.
MB_DEFBUTTON1
The first button is the default button.
MB_DEFBUTTON1 is the default unless MB_DEFBUTTON2, MB_DEFBUTTON3, or MB_DEFBUTTON4 is specified.
MB_DEFBUTTON2
The second button is the default button.
MB_DEFBUTTON3
The third button is the default button.
MB_DEFBUTTON4
The fourth button is the default button.
To indicate the modality of the dialog box, specify one of the following values.
MB_APPLMODAL
The user must respond to the message box before continuing work in the window identified by
the hWnd parameter. However, the user can move to the windows of other threads and work in
those windows.
Depending on the hierarchy of windows in the application, the user may be able to move to
other windows within the thread. All child windows of the parent of the message box are
automatically disabled, but pop-up windows are not.
MB_APPLMODAL is the default if neither MB_SYSTEMMODAL nor MB_TASKMODAL is specified.
MB_SYSTEMMODAL
Same as MB_APPLMODAL except that the message box has the WS_EX_TOPMOST style. Use system-modal
message boxes to notify the user of serious, potentially damaging errors that require immediate
attention (for example, running out of memory). This flag has no effect on the user's ability
to interact with windows other than those associated with hWnd.
MB_TASKMODAL
Same as MB_APPLMODAL except that all the top-level windows belonging to the current thread are
disabled if the hWnd parameter is NULL. Use this flag when the calling application or library
does not have a window handle available but still needs to prevent input to other windows in
the calling thread without suspending other threads.
To specify other options, use one or more of the following values.
MB_DEFAULT_DESKTOP_ONLY
Windows NT/2000/XP: Same as desktop of the interactive window station. For more information,
see Window Stations.
Windows NT 4.0 and earlier: If the current input desktop is not the default desktop,
MessageBox fails.
Windows 2000/XP: If the current input desktop is not the default desktop, MessageBox does not
return until the user switches to the default desktop.
Windows 95/98/Me: This flag has no effect.
MB_RIGHT
The text is right-justified.
MB_RTLREADING
Displays message and caption text using right-to-left reading order on Hebrew and Arabic systems.
MB_SETFOREGROUND
The message box becomes the foreground window. Internally, the system calls the
SetForegroundWindow function for the message box.
MB_TOPMOST
The message box is created with the WS_EX_TOPMOST window style.
MB_SERVICE_NOTIFICATION
Windows NT/2000/XP: The caller is a service notifying the user of an event. The function
displays a message box on the current active desktop, even if there is no user logged on to
the computer.
Terminal Services: If the calling thread has an impersonation token, the function directs
the message box to the session specified in the impersonation token.
If this flag is set, the hWnd parameter must be NULL. This is so that the message box can
appear on a desktop other than the desktop corresponding to the hWnd.
For more information on the changes between Microsoft Windows NT 3.51 and Windows NT 4.0,
see Remarks.
For information on security considerations in regard to using this flag, see Interactive Services.
MB_SERVICE_NOTIFICATION_NT3X
Windows NT/2000/XP: This value corresponds to the value defined for MB_SERVICE_NOTIFICATION for
Windows NT version 3.51.
For more information on the changes between Windows NT 3.51 and Windows NT 4.0, see Remarks.
RETURN VALUE
If a message box has a Cancel button, the function returns the IDCANCEL value if either the ESC key is
pressed or the Cancel button is selected. If the message box has no Cancel button, pressing ESC has no
effect.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
If the function succeeds, the return value is one of the following menu-item values.
IDABORT Abort button was selected.
IDCANCEL Cancel button was selected.
IDCONTINUE Continue button was selected.
IDIGNORE Ignore button was selected.
IDNO No button was selected.
IDOK OK button was selected.
IDRETRY Retry button was selected.
IDTRYAGAIN Try Again button was selected.
IDYES Yes button was selected.
*/