Usage of AfxMessageBox and MessageBox

Catalog

One 、AfxMessageBox

1. Function definition prototype

3.  Return value

Two 、MessageBox

1. Definition

​2. Parameter Introduction

3、 ... and 、 AfxMessageBox and MessageBox The difference between

1. Difference one

2. Difference two

3. Difference three

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One 、AfxMessageBox

    AfxMessageBox Is a functional prototype , The feature is the executable file of the application , The function is the text displayed inside the message box ,AfxMessageBox and CWnd Class member functions are similar to , It's easy to use , the reason being that Afx Framework based functions .

     about AfxMessageBox There are two definitions ：

1. Function definition prototype

To define a ：

int AfxMessageBox(
LPCTSTR lpszText,
UINT nType = MB_OK,
UINT nIDHelp = 0
);

Definition 2 ：

int AFXAPI AfxMessageBox(
UINT nIDPrompt,
UINT nType = MB_OK,
UINT nIDHelp = (UINT) –1
);

2. Parameter Introduction

[1]  Parameters 1

• In the first form ,lpszText Indicates the contents of the pop-up window , The title of the pop-up window is application EXE Executable file name （ Such as Hello）.

• In the second form ,nIDPrompt Is a text string ID. When the function is called, it will be automatically selected from the string table according to ID Load string display .

[2]  nType

• nType It is a combination of button style and icon style displayed in the message box , May adopt |（ or ） Operators combine various styles . Button styles include ：

MB_ABORTRETRYIGNORE	The message box displays Abort、Retry、Ignore Button
MB_OK	Show OK Button
MB_OKCANCEL	Show OK、Cancel Button
MB_RETRYCANCEL	Show Retry、Cancel Button
MB_YESNO	Show Yes、No Button
MB_YESNOCANCEL	Show Yes、No、Cancel Button

Example 1：MB_ABORTRETRYIGNORE 

int result = AfxMessageBox(L" Three Belle Wenzi ", MB_ABORTRETRYIGNORE);      //  suspend , retry , Ignore 
Show(result);    /*  Click abort   return 3,  Click Retry   return 4  Click ignore   return 5 */

Running results ：

Example 2：MB_OK 

int result = AfxMessageBox(L" Three Belle Wenzi ", MB_OK);
Show(result);          /*  Click ok   return 1 */

Running results ：

Example 3：MB_OKCANCEL 

int result = AfxMessageBox(L" Three Belle Wenzi ", MB_OKCANCEL);
Show(result);    /*  Click ok   return 1,  Click Cancel   return 2 */

Running results ：

Example 4：MB_RETRYCANCEL 

int result = AfxMessageBox(L" Three Belle Wenzi ", MB_RETRYCANCEL);
Show(result);    /*  Click Retry   return 4,  Click No   return 7  Click Cancel   return 2 */

Running results ：

Example 5：MB_YESNO 

int result = AfxMessageBox(L" Three Belle Wenzi ", MB_YESNO);
Show(result);  /*  Click is   return 6,  Click No   return 7 */

Running results ：

Example 6：MB_YESNOCANCEL

int result = AfxMessageBox(L" Three Belle Wenzi ", MB_YESNOCANCEL);
Show(result);  /*  Click is   return 6,  Click No   return 7  Click Cancel   return 2 */

Running results ：

[3]  nIDHelp

Icon style

MB_ICONINFORMATION	Display a i Icon , A hint
MB_ICONEXCLAMATION	Display an exclamation point , A warning
MB_ICONSTOP	Display the hand icon , Indicates a warning or serious error
MB_ICONQUESTION	Show the question mark icon , To express doubt

Example 1：MB_ICONINFORMATION 

AfxMessageBox(L" Three Belle Wenzi ", MB_ICONINFORMATION);

Running results ：

Example 2：MB_ICONEXCLAMATION 

AfxMessageBox(L" Three Belle Wenzi ", MB_ICONEXCLAMATION);

Running results ：

Example 3：MB_ICONSTOP 

AfxMessageBox(L" Three Belle Wenzi ", MB_ICONSTOP);

Running results ：

Example 4：MB_ICONQUESTION 

AfxMessageBox(L" Three Belle Wenzi ", MB_ICONQUESTION);

Running results ：

matters needing attention ：

If we just call ：

AfxMessageBox(LPCTSTR lpszText);

The system will default to ：

AfxMessageBox(LPCTSTR lpszText,MB_OK|MB_ICONEXCLAMATION );

3.  Return value

      The return value is 8 Kind of , If there's not enough memory , Then return to 0, Otherwise, one of the following values is returned , The corresponding buttons are clicked ：IDABORT、IDCANCEL、IDIGNORE、IDNO、IDOK 、IDRETRY、IDYES. The values of various return values are shown in the following table ：

ID	Select results	Return value
IDOK	OK	1
IDCANCEL	CANCEL	2
IDABORT	ABORT	3
IDRETRY	RETRY	4
IDIGNORE	IGNORE	5
IDYES	YES	6
IDNO	NO	7

Two 、MessageBox

    MessageBox It means to display a modal dialog , It contains a system icon 、 A set of buttons and a short application specific message , Information such as status or error . An integer value is returned in the message box , This value indicates which button the user clicked .

1. Definition

To define a ：

WINUSERAPI int WINAPI MessageBoxA(
HWND hWnd,
LPCSTR lpText,
LPCSTR lpCaption,
UINT uType);

  Definition 2 ：

WINUSERAPI int WINAPI MessageBoxW(
HWND hWnd,
LPCWSTR lpText,
LPCWSTR lpCaption,
UINT uType);

​2. Parameter Introduction

[1] hWnd

This parameter represents the window owned by the message box . If NULL, Then the message box does not have a window .

[2] lpText

The contents of the message box . If used Unicode library , Turn the text into ：

TEXT(/*sometext*/)

[3] lpCaption

The title of the message box . If used Unicode library , Turn the text into ：

TEXT(/*sometext*/)

​​ Example 1： MessageBox

MessageBox(TEXT(" Three Belle Wenzi "), TEXT("Serven Warning "), MB_TASKMODAL);​

Running results ：

You can set your own title

 [4] uType

Specify a set of bit flags that determine the content and behavior of the dialog box . This parameter can be a combination of flags in the following flag groups . Specify one of the following flags to display the buttons and icons in the message box .

Button parameters	meaning
MB_OK	The default value is . There is a confirmation button inside .
MB_YESNO	Yes or no in it .
MB_ABORTRETRYIGNORE	Yes Abort（ give up ）,Retry（ retry ） and Ignore（ skip ）
MB_YESNOCANCEL	The message box contains three buttons ：Yes,No and Cancel
MB_RETRYCANCEL	Yes Retry（ retry ） and Cancel（ Cancel ）
MB_OKCANCEL	The message box contains two buttons ：OK and Cancel

Icon ：

Parameters	meaning
MB_ICONEXCLAMATION	An exclamation point appears in the message box
MB_ICONWARNING	An exclamation point appears in the message box
MB_ICONINFORMATION	Write small letters in a circle i The icon of the composition appears in the message box
MB_ICONASTERISK	Write small letters in a circle i The icon of the composition appears in the message box
MB_ICONQUESTION	A problem marker icon appears in the message box
MB_ICONSTOP	A stop message icon appears in the message box
MB_ICONERROR	A stop message icon appears in the message box
MB_ICONHAND	A stop message icon appears in the message box

form ：

Parameters	meaning
MB_APPLMODAL	stay hwnd Before continuing work in the window identified by the parameter , The user must respond to the message box . however , Users can move to windows of other threads and work in these windows . According to the hierarchical structure of the window in the application , The user moves to other windows in the thread . All child windows of the parent message box automatically expire , But pop ups are not like this . If neither MB_SYSTEMMODAL There is no designation MB_TASKMOOAL, be MB_APPLMODAL For the default .
MB_SYSTEMMODAL	Except for the message box WB_EX_TOPMOST type ,MB_APPLMODAL and MB_SYSTEMMODAL equally . Use the system modal message box to change all kinds of users , Major damage errors require immediate attention （ for example , out of memory ）. With those if not hwnd Contact window , This flag has no effect on the user's interaction with the window .
MB_TASKMODAL	If parameters hwnd by NULL Words , Then, except that all windows belonging to the high-level of the current thread fail ,MB_TASKMODALL and MB_APPLMODAL equally . When the calling application or library does not have a window handle available , Use this sign . But you still need to block input to other windows of the calling thread , Instead of shelving other threads .

other ：

sign	meaning
MB_DEFAULT_DESKTOP_ONLY	The current desktop receiving input must be a default desktop . otherwise , Function call failed . The default desktop is a desktop on which the user has recorded and on which the application will run in the future .
MB_HELP	Put one Help The button is added to the message box . choice Help Button or press F1 Produce a Help event .
MB_RIGHT	Text is right adjusted
MB_RTLREADING	Use in Hebrew and Arabic Messages and uppercase text are displayed in the system from right to left .
MB_SETFOREGROUND	The message box becomes the foreground window . Make a call for the message in the internal system SetForegroundWindow function .
MB_TOPMOST	The message box uses WS_EX_TOPMOST Window type to create MB_SERVICE_NOTIFICATION.

Return value ：

ID	Select results	Return value
IDOK	OK	1
IDCANCEL	CANCEL	2
IDABORT	ABORT	3
IDRETRY	RETRY	4
IDIGNORE	IGNORE	5
IDYES	YES	6
IDNO	NO	7

Let's see how the source code defines the above ：

// Button 
#define MB_OK 0x00000000L
#define MB_OKCANCEL 0x00000001L
#define MB_ABORTRETRYIGNORE 0x00000002L
#define MB_YESNOCANCEL 0x00000003L
#define MB_YESNO 0x00000004L
#define MB_RETRYCANCEL 0x00000005L
// Icon 
#define MB_ICONHAND 0x00000010L
#define MB_ICONQUESTION 0x00000020L
#define MB_ICONEXCLAMATION 0x00000030L
#define MB_ICONASTERISK 0x00000040L
#define MB_USERICON 0x00000080L
// Icon declaration 
#define MB_ICONWARNINGMB_ICONEXCLAMATION
#define MB_ICONERRORMB_ICONHAND
#define MB_ICONINFORMATIONMB_ICONASTERISK
#define MB_ICONSTOPMB_ICONHAND
// Default button declaration 
#define MB_DEFBUTTON1 0x00000000L
#define MB_DEFBUTTON2 0x00000100L
#define MB_DEFBUTTON3 0x00000200L
#if(WINVER>=0x0400)
#define MB_DEFBUTTON4 0x00000300L// If you support the fourth MessageBox Button words , Definition DEFButton4
#endif
// Dialog model definition 
#define MB_APPLMODAL 0x00000000L
#define MB_SYSTEMMODAL 0x00001000L
#define MB_TASKMODAL 0x00002000L
#define MB_HELP 0x00004000L// Whether there is a help button 
// Special statement 
#define MB_NOFOCUS 0x00008000L
#define MB_SETFOREGROUND 0x00010000L
#define MB_DEFAULT_DESKTOP_ONLY 0x00020000L
#define MB_TOPMOST 0x00040000L
#define MB_RIGHT 0x00080000L
#define MB_RTLREADING 0x00100000L

3、 ... and 、 AfxMessageBox and MessageBox The difference between

     So much has been said , that AfxMessageBox and MessageBox What's the difference ？

1. Difference one

    MessageBox() It's standard Win32 API function , You can use it directly ;AfxMessageBox yes MFC Global functions provided by the library , Provides a variety of overloaded forms , need MFC Framework support （ with afx Are framework based functions ）. So in Win32 SDK Under the circumstances , Only use MessageBox（ here MessageBox use Win 32 Prototype in ,hWnd Set to NULL）; And in the MFC in , Both can be used （ here MessageBox use MFC Prototype in , stay CWnd Class or subclass ）, But it's best to use it as much as possible AfxMessageBox, Here's why ：

（1） stay MFC Can be used in MessageBox() All the places can be used AfxMessageBox(), That is to say, the latter can be used instead of the former ;

（2）AfxMessageBox This global function is the safest , It is also the most simple and convenient , Because it is a global function, it does not need a corresponding window class .

2. Difference two

    MessageBox More formal , Often used in application versions to be submitted , You can control the content of the title , You don't have to use an ambiguous executable name as the title （ At this point ,MessageBox Than AfxMessageBox flexible , It can set any title , and AfxMessageBox You can't ）.

    AfxMessageBox Cannot control message box title , It is often used for internal data output or warning when debugging programs （ More often, it is used for debugging ）.

3. Difference three

    MessageBox stay Win 32 Prototype in , If the first parameter hWnd Set to NULL, Then the generated modeless dialog ;AfxMessageBox What is generated is a modal dialog , The program will not run until you confirm it , It will block your current thread , Unless your program is multithreaded , Otherwise, only wait for the modal dialog box to be confirmed .