int WINAPI MessageBox
(
  _In_opt_ HWND    hWnd,
  _In_opt_ LPCTSTR lpText,
  _In_opt_ LPCTSTR lpCaption,
  _In_     UINT    uType
);

Parameters 參數

hWnd [in, optional] 窗口句柄

Type（類型）: HWND

A handle to the owner window of the message box to be created. If this parameter is NULL, the message box has no owner window.

這個句柄屬於創建這個MessageBox的窗體的句柄，如果為空，則沒有，默認是以桌面為父窗口。

lpText [in, optional] 內容

Type（類型）: LPCTSTR

The message to be displayed. 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.

顯示對話框消息內容，如果有多行，用回車換行符（\r \n）分成多行。

lpCaption [in, optional] 標題

Type（類型）: LPCTSTR

The dialog box title. If this parameter is NULL, the default title is Error.

顯示對話框標題，如果參數是NULL，則默認標題為Error。

---

uType [in]

Type: UINT

The contents and behavior of the dialog box. This parameter can be a combination of flags from the following groups of flags.

這個參數表明這個對話框的內容和行為。這個參數可以由一個標誌和一個標誌組組成。

To indicate the buttons displayed in the message box, specify one of the following values.

要想指明這個消息框的顯示按鈕，需要確定下列的值。

Value	Meaning
MB_ABORTRETRYIGNORE 0x00000002L	The message box contains three push buttons: Abort, Retry, and Ignore. 這個消息框包含三個按鈕：Abort，Retry,Ignore.
MB_CANCELTRYCONTINUE 0x00000006L	The message box contains three push buttons: Cancel, Try Again, Continue. Use this message box type instead of MB_ABORTRETRYIGNORE. 這個消息框包含三個按鈕：Cancek,Try Again,Continue.可以用MB_ABORTRETRYIGNORE代替。
MB_HELP 0x00004000L	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. 給消息框添加一個Help Button.當用戶點擊這個按鈕或者按下F1時，系統會向他的父窗口發送一條WM_HTLP消息。
MB_OK 0x00000000L	The message box contains one push button: OK. This is the default. 給消息框添加一個OK按鈕，如果為NULL，默認就是MB_OK。
MB_OKCANCEL 0x00000001L	The message box contains two push buttons: OK and Cancel.
MB_RETRYCANCEL 0x00000005L	The message box contains two push buttons: Retry and Cancel.
MB_YESNO 0x00000004L	The message box contains two push buttons: Yes and No.
MB_YESNOCANCEL 0x00000003L	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.

消息框添加展示圖標，需要確定以下的值：

Value	Meaning
MB_ICONEXCLAMATION 0x00000030L	An exclamation-point icon appears in the message box. 顯示一個驚嘆號圖標。
MB_ICONWARNING 0x00000030L	An exclamation-point icon appears in the message box.
MB_ICONINFORMATION 0x00000040L	An icon consisting of a lowercase letter i in a circle appears in the message box. 這個消息框裏面有一個：圓圈裏面包含小寫字母i.
MB_ICONASTERISK 0x00000040L	An icon consisting of a lowercase letter i in a circle appears in the message box.
MB_ICONQUESTION 0x00000020L	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. 一個問號圖標在消息框上。系統任然支持這個圖標，但是不建議使用它，因為，它象征一個不明確的類型。
MB_ICONSTOP 0x00000010L	A stop-sign icon appears in the message box. 一個stop符號的圖標。
MB_ICONERROR 0x00000010L	A stop-sign icon appears in the message box.
MB_ICONHAND 0x00000010L	A stop-sign icon appears in the message box.

To indicate the default button, specify one of the following values.

制定默認按鈕，需要確定以下的值：

Value	Meaning
MB_DEFBUTTON1 0x00000000L	The first button is the default button. MB_DEFBUTTON1 is the default unless MB_DEFBUTTON2, MB_DEFBUTTON3, or MB_DEFBUTTON4 is specified. 這個是默認按鈕，MB_DEFBUTTON2, MB_DEFBUTTON3, or MB_DEFBUTTON4除非被添加。
MB_DEFBUTTON2 0x00000100L	The second button is the default button.
MB_DEFBUTTON3 0x00000200L	The third button is the default button.
MB_DEFBUTTON4 0x00000300L	The fourth button is the default button.

To indicate the modality of the dialog box, specify one of the following values.

指定這個對話框的模式，需要確定以下的值：

Value	Meaning
MB_APPLMODAL 0x00000000L	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. 用戶必須響應消息框在hWnd參數被確定下來之前，用戶可以移動其他線程的窗口和當前工作窗口。 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. 依賴於這個程序的窗口繼承，用戶可以移動其他包含線程的窗口。所有的父窗口的子窗口是自動顯示的，但是右鍵窗口不是。 MB_APPLMODAL is the default if neither MB_SYSTEMMODAL nor MB_TASKMODAL is specified. MB_APPLMODAL是默認參數，除非MB_SYSTEMMODAL和MB_TASKMODAL被添加。
MB_SYSTEMMODAL 0x00001000L	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 0x00002000L	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.

Value	Meaning
MB_DEFAULT_DESKTOP_ONLY 0x00020000L	Same as desktop of the interactive window station. For more information, see Window Stations. If the current input desktop is not the default desktop, MessageBox does not return until the user switches to the default desktop.
MB_RIGHT 0x00080000L	The text is right-justified.
MB_RTLREADING 0x00100000L	Displays message and caption text using right-to-left reading order on Hebrew and Arabic systems.
MB_SETFOREGROUND 0x00010000L	The message box becomes the foreground window. Internally, the system calls the SetForegroundWindow function for the message box.
MB_TOPMOST 0x00040000L	The message box is created with the WS_EX_TOPMOST window style.
MB_SERVICE_NOTIFICATION 0x00200000L	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 information on security considerations in regard to using this flag, see Interactive Services. In particular, be aware that this flag can produce interactive content on a locked desktop and should therefore be used for only a very limited set of scenarios, such as resource exhaustion.

太多啦慢慢搞！！！

MessageBox