Determining Which Mouse Buttons Are Pressed in the Click Event Handler

Although the e parameter is typed as EventArgs in the event handler’s signature, it contains a MouseEventArgs object exposing information about the buttons being pressed when the event handler gets called. The code sample below displays information about the mouse buttons when the user clicks a form:

Private Sub Form_Click( _
    ByVal sender As Object, _
    ByVal e As EventArgs _
) Handles MyBase.Click
    If TypeOf e Is MouseEventArgs Then
         Dim Args As MouseEventArgs = DirectCast(e, MouseEventArgs)
    End If
End Sub

Some controls like the button control will only raise the Click event if the left mouse button is pressed and thus won’t reveal this information for clicks with other mouse buttons.