Displays a specified message to the user.
function MessageBox(const Text, Caption: PChar; Flags: Longint = MB_OK): Integer;
Description
Use MessageBox to display a generic dialog box a message and one or more buttons. Caption is the caption of the dialog box and is optional.
MessageBox is an encapsulation of the Windows
API MessageBox function. TApplication’s encapsulation of MessageBox automatically supplies the missing window
handle parameter needed for the Windows
API function.
The value of the Text parameter is the message, which can be longer than 255 characters if necessary. Long messages are automatically wrapped in the message box.
The value of the Caption parameter is the caption that appears in the title bar of the dialog box. Captions can be longer than 255 characters, but don't wrap. A long caption results in a wide message box.
The Flags parameter specifies what buttons appear on the message box and the behavior (possible return values). The following table lists the possible values. These values can be combined to obtain the desired effect.
Value Meaning
MB_ABORTRETRYIGNORE The message box contains three push buttons: Abort, Retry, and Ignore.
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.
MessageBox returns 0 if there isn’t enough memory to create the message box. Otherwise it returns one of the following values:
Value Numeric value Meaning
IDOK 1 The user chose the OK button.
IDCANCEL 2 The user chose the Cancel button.
IDABORT 3 The user chose the Abort button.
IDRETRY 4 The user chose the Retry button.
IDIGNORE 5 The user chose the Ignore button.
IDYES 6 The user chose the Yes button.
IDNO 7 The user chose the No button.