C# Message Box

C# MessageBox in Windows Forms displays a message with the given text and action buttons. You can also use MessageBox control to add additional options such as a caption, an icon, or help buttons. In this article, you'll learn how to display and use a MessageBox in C# WinForms app. You will also learn how to use C# MessageBox class dynamically in code samples.

C# MessageBox

MessageBox class has an overloaded static Show method that displays a message box with a message and action buttons. The action buttons can be OK and Cancel, Yes and No etc. Here are some of the options that can be used in C# message box.

Simple MessageBox

The simplest form of a MessageBox is a dialog with text and OK button. When you click OK button, the box disappears.

The following code snippet creates a simple Message Box.

string message = "Simple MessageBox";  
MessageBox.Show(message);

MessageBox with Title

The following code snippet creates a simple MessageBox with a title.

string message = "Simple MessageBox";  
string title = "Title";  
MessageBox.Show(message, title); 

MessageBox with Buttons

A MessageBox can have different button combinations such as YesNo and OKCancel. The MessageBoxButtons enumeration represents the buttons to be displayed on a MessageBox and has following values.

• OK
• OKCancel
• AbortRetryIgnore
• YesNoCancel
• YesNo
• RetryCancel

The following code snippet creates a MessageBox with a title and Yes and No buttons. This is a typical MessageBox you may call when you want to close an application. If the Yes button is clicked, the application will be closed. The Show method returns a DialogResult enumeration.

string message = "Do you want to close this window?";  
string title = "Close Window";  
MessageBoxButtons buttons = MessageBoxButtons.YesNo;  
DialogResult result = MessageBox.Show(message, title, buttons);  
if (result == DialogResult.Yes) {  
    this.Close();  
} else {  
    // Do something  
}

MessageBox with Icon

A MessageBox can display an icon on the dialog. A MessageBoxIcons enumeration represents an icon to be displayed on a MessageBox and has the following values.

• None
• Hand
• Question
• Exclamation
• Asterisk
• Stop
• Error
• Warning
• Information

The following code snippet creates a MessageBox with a title, buttons, and an icon.

string message = "Do you want to abort this operation?";  
string title = "Close Window";  
MessageBoxButtons buttons = MessageBoxButtons.AbortRetryIgnore;  
DialogResult result = MessageBox.Show(message, title, buttons, MessageBoxIcon.Warning);  
if (result == DialogResult.Abort) {  
    this.Close();  
}  
elseif(result == DialogResult.Retry) {  
    // Do nothing  
}  
else {  
    // Do something  
}

MessageBox with Default Button

We can also set the default button on a MessageBox. By default, the first button is the default button. The MessageBoxDefaultButton enumeration is used for this purpose and it has the following three values.

• Button1
• Button2
• Button3

The following code snippet creates a MessageBox with a title, buttons, and an icon and sets the second button as a default button.

string message = "Do you want to abort this operation?";  
string title = "Close Window";  
MessageBoxButtons buttons = MessageBoxButtons.AbortRetryIgnore;  
DialogResult result = MessageBox.Show(message, title, buttons, MessageBoxIcon.Warning, MessageBoxDefaultButton.Button2);  
if (result == DialogResult.Abort) {  
    this.Close();  
}  
elseif(result == DialogResult.Retry) {  
    // Do nothing  
}  
else {  
    // Do something  
}

MessageBox with Message Options

MessageBoxOptions enumeration represents various options and has the following values.

• ServiceNotification
• DefaultDesktopOnly
• RightAlign
• RtlReading

The following code snippet creates a MessageBox with various options.

DialogResult result = MessageBox.Show(message, title, buttons,  
MessageBoxIcon.Warning, MessageBoxDefaultButton.Button2,  
MessageBoxOptions.RightAlign|MessageBoxOptions.RtlReading);  

MessageBox with Help Button

A MessageBox can have an extra button called Help button. This is useful when we need to display a help file. The following code snippet creates a MessageBox with a Help button.

DialogResult result = MessageBox.Show(message, title, buttons,  
MessageBoxIcon.Warning, MessageBoxDefaultButton.Button2,  
MessageBoxOptions.RightAlign, true );  

We can also specify a help file when the Help button is clicked. The following code snippet references a help file.

DialogResult result = MessageBox.Show(message, title,  
buttons, MessageBoxIcon.Question, MessageBoxDefaultButton.Button1, 0, "helpfile.chm");  

Summary

In this article, we discussed how to create and use a MessageBox in a Windows Forms application.