INF: Creating a Multiple Line Message Box

ID Number: Q67210

2.00 2.03 2.10 3.00

WINDOWS

Summary:

Message boxes are used to provide information to the user of an

application. Error messages and warnings are also provided through

message boxes. This article provides details on using message boxes in

applications.

More Information:

Message boxes are modal windows. When an application displays an

application modal message box, which is the default message box type,

the user cannot interact with any part of that application until the

message box has been dismissed. However, the user may use the mouse or

keyboard to activate another application and interact with it while

the message box is displayed. Certain critical errors that may affect

all of Windows are displayed in system modal message boxes. Windows

will not perform any operations until the error condition is

acknowledged and the system modal message box is dismissed.

There are times where it is necessary to display a long message in a

message box. Windows does this when you start a DOS application that

uses graphics from inside a DOS window. To break a message into many

lines, insert a newline character into the message text. Here is a

sample MessageBox() call:

MessageBox(hWnd, "This is line 1.\nThis is line 2.", "App",

MB_OK | MB_ICONQUESTION);

If the text of a message is too long for a single line, Windows will

break the text into multiple lines.

System modal message boxes treat the newline character as any other. A

newline character is displayed as a black block in the text. Because

system modal message boxes are designed to work at all times, even

under extremely low memory conditions, it does not provide the ability

to display more than one line of text.