A Button can be clicked by using the mouse, ENTER key, or SPACEBAR if the button has focus.

Set the AcceptButton or CancelButton property of a Form to allow users to click a button by pressing the ENTER or ESC keys even if the button does not have focus. This gives the form the behavior of a dialog box.

When you display a form using the ShowDialog method, you can use the DialogResult property of a button to specify the return value of ShowDialog.

You can change the button's appearance. For example, to make it appear flat for a Web look, set the FlatStyle property to FlatStyle.Flat. The FlatStyle property can also be set to FlatStyle.Popup, which appears flat until the mouse pointer passes over the button; then the button takes on the standard Windows button appearance.

Note
If the control that has focus accepts and processes the ENTER key press, the Button does not process it. For example, if a multiline TextBox or another button has focus, that control processes the ENTER key press instead of the accept button.