The MsgBox function and MessageBox class both display message dialog boxes in Visual Basic. MsgBox is a function that displays a message, waits for a button click, and returns a response. MessageBox is a class with various Show methods that accomplish the same functionality. Both accept parameters to customize the buttons, title, icon, and default response. They provide an easy way to prompt users and receive feedback in message box dialogs.

1. The MsgBox Function and the MessageBox Class
• MsgBox function, is a part of the
Microsoft.VisualBasic namespace .
• MessageBox is the class. Part of
System.Windows.MessageBox

2. The MsgBox Function
• The MsgBox function displays a message in a dialog box,
waits for the user to click a button, and returns an Integer
indicating which button the user clicked.
• Syntax:
– MsgBox(prompt[, buttons] [, title])
– - or –
– IntegerVariable = MsgBox(prompt[, buttons] [, title])
• The MsgBox function syntax has these parts:
• Part
• prompt
– Required. String expression displayed as the message in the
dialog box. The maximum length of prompt is approximately
1024 characters, depending on the width of the characters
used.

3. • buttons
– Optional. Numeric expression that is the sum of values
specifying the number and type of buttons to display, the
icon style to use, the identity of the default button, and
the modality of the message box. If omitted, the default
value for buttons is 0 (which causes only an OK button to
be displayed with no icon). The buttons argument is
explained in more detail below.
• title
– Optional. String expression displayed in the title bar of the
dialog box. If you omit title, the application name is placed
in the title bar.

4. The buttons argument
• The buttons argument is formed by five groups of values.
• The first group of values (0–5) describes the number and type of buttons
displayed in the dialog box;
• The second group (16, 32, 48, 64) describes the icon style;
• The third group (0, 256, 512, 768) determines which button is the default;
• The fourth group (0, 4096) determines the modality of the message box;
• And the fifth group contains values that would only be used under special
circumstances.
• When adding numbers to create a final value for the buttons argument,
use only one number from each group.
• For each value, a corresponding built-in constant i.e. either the classic
"vb" constants or the .NET "MsgBoxStyle" enumeration constants may
also be used.
• Use of the constants is preferred for readability.
• The "vb" constants were introduced in earlier versions of Visual Basic and
may also be used in VB.NET.
• VB.NET also provides the "MsgBoxStyle" enumeration constants which
can be used as an alternative to the "vb" constants.

5. First Group: Determines which buttons to display:
Constant Value Description
vbOKOnly 0 Display OK button only.
- or -
MsgBoxStyle.OKOnly
vbOKCancel 1 Display OK and Cancel
- or - buttons.
MsgBoxStyle.OKCancel
vbAbortRetryIgnore 2 Display Abort, Retry,
- or - and Ignore buttons.
MsgBoxStyle.AbortRetryIg
nore
vbYesNoCancel 3 Display Yes, No, and
- or - Cancel buttons.
MsgBoxStyle.YesNoCanc
el
vbYesNo 4 Display Yes and No
- or - buttons.
MsgBoxStyle.YesNo
vbRetryCancel 5 Display Retry and
- or - Cancel buttons.
MsgBoxStyle.RetryCancel

6. Second Group:Determines which icon to display:
Constant Value Description Icon
vbCritical 16 Display Critical
- or - Message icon.
MsgBoxStyle.Cri
tical
vbQuestion 32 Display
- or - Warning Query
MsgBoxStyle.Qu (question mark)
estion icon.
vbExclamation 48 Display
- or - Warning
MsgBoxStyle.Ex Message icon.
clamation
vbInformation 64 Display
- or - Information
MsgBoxStyle.Inf Message icon.
ormation

7. Third Group:Determines which button is the
default:
Constant Value Description
vbDefaultButton1 0 First button is default.
- or -
MsgBoxStyle.DefaultButt
on1
vbDefaultButton2 256 Second button is default.
- or -
MsgBoxStyle.DefaultButt
on2
vbDefaultButton3 512 Third button is default.
- or -
MsgBoxStyle.DefaultButt
on3
vbDefaultButton4 768 Fourth button is default
- or - (applicable only if a Help
MsgBoxStyle.DefaultButt button has been added).
on4

8. Fourth Group:
Determines the modality of the message box.
Generally, you would not need to use a constant from this group, as you would want
to use the default (application modal). If you specified "system modal", you would be
"hogging" Windows – i.e., if a user had open another app , like Word or Excel, they
would not be able to get back to it until they responded to your app's message box.
Constant Value Description
vbApplicationModal 0 Application modal; the
- or - user must respond to
MsgBoxStyle.Applicati the message box
onModal before continuing work
in the current
application.
vbSystemModal 4096 System modal; all
- or - applications are
MsgBoxStyle.System suspended until the
Modal user responds to the
message box.

9. The fifth group of constants that can be used for the buttons argument would
only be used under special circumstances:
Constant Value Description
vbMsgBoxHelpButton 16384 Adds Help button to the
- or - message box
MsgBoxStyle.MsgBoxHel
pButton
vbMsgBoxSetForeground 65536 Specifies the message
- or - box window as the
MsgBoxStyle.MsgBoxSet foreground window
Foreground
vbMsgBoxRight 524288 Text is right aligned
- or -
MsgBoxStyle.MsgBoxRig
ht
vbMsgBoxRtlReading 1048576 Specifies text should
- or - appear as right-to-left
MsgBoxStyle.MsgBoxRtl reading on Hebrew and
Reading Arabic systems

10. • When you use MsgBox with the option to display
more than one button (i.e., from the first group,
anything other than "vbOKOnly"), you can test
which button the user clicked by comparing the
return value of the Msgbox function with one of
these values.
• For each return value, a corresponding built-in
constant (either the classic "vb" constants or
the .NET "MsgBoxResult" enumeration constants)
may also be used.
• VB.NET also provides the "MsgBoxResult"
enumeration constants which can be used as an
alternative to the "vb" constants.
•

11. Msgbox constants
Constant Value Description
vbOK 1 The OK button was
-or- pressed
MsgBoxResult.OK
vbCancel 2 The Cancel button was
-or- pressed
MsgBoxResult.Cancel
vbAbort 3 The Abort button was
-or- pressed
MsgBoxResult.Abort
vbRetry 4 The Retry button was
-or- pressed
MsgBoxResult.Retry

12. vbIgnore 5 The Ignore button was
-or- pressed
MsgBoxResult.Ignore
vbYes 6 The Yes button was
-or- pressed
MsgBoxResult.Yes
vbNo 7 The No button was
-or- pressed
MsgBoxResult.No

13. MessageBox Class
• As an alternative, .NET has introduced a class called
MessageBox which encapsulates all the features of
MsgBox.
• The difference between MsgBox and MessageBox is that
Msgbox is a function while MessageBox is a class.
• The MessageBox class has various overloaded Show
methods for different parameters.
• From a practical standpoint, both the MsgBox function and
the MessageBox class will accomplish the same thing.
• The arguments for MessageBox are specified in a slightly
different order from MsgBox.
• MessageBox.Show Method
• To show the message box we need to call the Show
method of the MessageBox class, for example:
-MessageBox.Show("Hello World!")

14. • The Show method has various overloaded
forms.
• syntax
– [DialogResult = ] MessageBox.Show([window ,]
- prompt
– [, caption]
– [, MessageBoxButtons]
– [, MessageBoxIcon]
– [, MessageBoxDefaultButton]
– [, MessageBoxOptions])

15. window The window that the message box will
display in front of (for example, you
could specify "Me" to refer to the current
form). This argument is typically omitted.
prompt The text to display in the message box. This
is the only required argument
caption The text to display in the title bar of the
message box. If omitted, the project name
will be displayed.

16. MessageBoxButtons Specifies which buttons to display on
the message box. Possible values are:
•MessageBoxButtons.AbortRetryIgnore
(displays the Abort, Retry, and Ignore
buttons)
•MessageBoxButtons.OK (displays the
OK button)
•MessageBoxButtons.OKCancel
(displays the OK and Cancel buttons)
•MessageBoxButtons.RetryCancel
(displays the Retry and Cancel buttons)
•MessageBoxButtons.YesNo (displays
the Yes and No buttons)
•MessageBoxButtons.YesNoCancel
(displays the Yes, No, and Cancel
buttons)

17. MessageBoxIcon Specifies which icon to display on
the message box. Possible values
are:
Value Icon
MessageBoxIcon.Error
- or -
MessageBoxIcon.Hand
- or -
MessageBoxIcon.Stop
MessageBoxIcon.Question
MessageBoxIcon.Exclamatio
n
- or -
MessageBoxIcon.Warning
MessageBoxIcon.Asterisk
- or -
MessageBoxIcon.Informatio
n
(none)
MessageBoxIcon.None

18. MessageBoxDefaultButton Specifies the default button for the message
box. Possible values are:
• MessageBoxDefaultButton.Button1 (the
first message box button is the default button)
• MessageBoxDefaultButton.Button2 (the
second message box button is the default
button)
• MessageBoxDefaultButton.Button3 (the
third message box button is the default
button)
MessageBoxOptions Allows specialized options to be specified.
Possible values are:
•
MessageBoxOptions.DefaultDesktopOnly
(displays the message box on the active desktop)
• MessageBoxOptions.RightAlign (displays
the message box text right-aligned)
• MessageBoxOptions.RtlReading
(displays the text in right-to-left reading order)
• MessageBoxOptions.ServiceNotification
(displays the message box on the active desktop,
even if there is no user logged on to the computer

19. Value Description
DialogResult.OK The OK button was pressed
DialogResult.Cancel The Cancel button was pressed
DialogResult.Abort The Abort button was pressed
DialogResult.Retry The Retry button was pressed
DialogResult.Ignore The Ignore button was pressed
DialogResult.Yes The Yes button was pressed
DialogResult.No The No button was pressed
DialogResult.None Nothing is returned from the dialog
box. This means that the modal dialog
continues running.

20. InputBox( ) function
• An InputBox( ) function will display a message box where the user
can enter a value or a message in the form of text.
• Syntax
– myMessage=InputBox(Prompt, Title, default_text, x-position, y-
position)
• myMessage is a string type but which accept the message input by
the users. The arguments are explained as follows:
• Prompt - The message displayed normally as a question asked.
• Title - The title of the Input Box.
• default-text - The default text that appears in the input field where
users can use it as his intended input or he may change to the
message he wish to enter.
• x-position and y-position - the position or the coordinates of the
input box.

21. • Private Sub Button7_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs)
Handles Button7.Click
• Dim r As String
• r = InputBox("hi", "demo", "fun", 50, 70)
• End Sub