Interaction.MsgBox(Object, MsgBoxStyle, Object) Method


Displays a message in a dialog box, waits for the user to click a button, and then returns an integer indicating which button the user clicked.

public static Microsoft.VisualBasic.MsgBoxResult MsgBox (object Prompt, Microsoft.VisualBasic.MsgBoxStyle Buttons = Microsoft.VisualBasic.MsgBoxStyle.OkOnly, object? Title = default);
public static Microsoft.VisualBasic.MsgBoxResult MsgBox (object Prompt, Microsoft.VisualBasic.MsgBoxStyle Buttons = Microsoft.VisualBasic.MsgBoxStyle.ApplicationModal, object Title = default);
static member MsgBox : obj * Microsoft.VisualBasic.MsgBoxStyle * obj -> Microsoft.VisualBasic.MsgBoxResult
Public Function MsgBox (Prompt As Object, Optional Buttons As MsgBoxStyle = Microsoft.VisualBasic.MsgBoxStyle.OkOnly, Optional Title As Object = Nothing) As MsgBoxResult
Public Function MsgBox (Prompt As Object, Optional Buttons As MsgBoxStyle = Microsoft.VisualBasic.MsgBoxStyle.ApplicationModal, Optional Title As Object = Nothing) As MsgBoxResult



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. If Prompt consists of more than one line, you can separate the lines using a carriage return character (Chr(13)), a line feed character (Chr(10)), or a carriage return/linefeed character combination (Chr(13) & Chr(10)) between each line.


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 you omit Buttons, the default value is zero.


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.


One of the following values:



Prompt is not a String expression, or Title is invalid.

Process is not running in User Interactive mode.

One or more parameters not a member of MsgBoxResult or MsgBoxStyle enumeration.


This example uses the MsgBox function to display a critical-error message in a dialog box with Yes and No buttons. The No button is specified as the default response. This is done by combining the MsgBox constant values into one numeric expression. In this case, adding 4 (the Yes/No button combination) and 16 (the Critical Message window) and 256 (the second button as default button) gives a total of 276. The value returned by the MsgBox function depends on the button chosen by the user: Yes returns a value of 6; No returns a value of 7.

' The following example requires that Option Infer be set to On.

' Define the message you want to see inside the message box.
Dim msg = "Do you want to continue?"

' Display a simple message box.

' Define a title for the message box.
Dim title = "MsgBox Demonstration"

' Add the title to the display.
MsgBox(msg, , title)

' Now define a style for the message box. In this example, the
' message box will have Yes and No buttons, the default will be
' the No button, and a Critical Message icon will be present.
Dim style = MsgBoxStyle.YesNo Or MsgBoxStyle.DefaultButton2 Or

' Display the message box and save the response, Yes or No.
Dim response = MsgBox(msg, style, title)

' Take some action based on the response.
If response = MsgBoxResult.Yes Then
    MsgBox("YES, continue!!", , title)
    MsgBox("NO, stop!!", , title)
End If


If you omit any positional arguments, you must retain the corresponding comma delimiter.

If the dialog box displays a Cancel button, pressing the ESC key has the same effect as clicking Cancel

If the dialog box contains a Help button, context-sensitive Help is provided for the dialog box. However, no value is returned until one of the other buttons is chosen. In Windows Form applications, choosing the Help button executes the HelpRequested event for the form.


The MsgBox function requires UIPermission at the SafeTopLevelWindows level, which may affect its execution in partial-trust situations. For more information, see UIPermission.

The MsgBoxStyle enumeration values are listed in the following table.

Member Value Description
Member Value Description
OKOnly 0 Displays OK button only.
OKCancel 1 Displays OK and Cancel buttons.
AbortRetryIgnore 2 Displays Abort, Retry, and Ignore buttons.
YesNoCancel 3 Displays Yes, No, and Cancel buttons.
YesNo 4 Displays Yes and No buttons.
RetryCancel 5 Displays Retry and Cancel buttons.
Critical 16 Displays Critical Message icon.
Question 32 Displays Warning Query icon.
Exclamation 48 Displays Warning Message icon.
Information 64 Displays Information Message icon.
DefaultButton1 0 First button is default.
DefaultButton2 256 Second button is default.
DefaultButton3 512 Third button is default.
ApplicationModal 0 Application is modal. The user must respond to the message box before continuing work in the current application.
SystemModal 4096 System is modal. All applications are suspended until the user responds to the message box.
MsgBoxSetForeground 65536 Specifies the message box window as the foreground window.
MsgBoxRight 524288 Text is right-aligned.
MsgBoxRtlReading 1048576 Specifies text should appear as right-to-left reading on Hebrew and Arabic systems.

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) determines which button is the default. The fourth group (0, 4096) determines the modality of the message box, and the fifth group specifies whether or not the message box window is the foreground window, along with the alignment and direction of the text. When adding numbers to create a final value for the Buttons argument, use only one number from each group.

Applies to

See also