Public Class Form1
    Dim WithEvents Btn As New Button With {.Dock = DockStyle.Bottom, .Text = _
      "Start", .Parent = Me}
    Dim Button(9) As Button
    Dim rnd As New Random
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        Me.Height = 500
        For i As Int32 = 0 To 9
            Button(i) = New Button
            Button(i).Name = "Button" & (1 + i).ToString
            Button(i).Text = Button(i).Name
            Button(i).SetBounds(110, 15 + 35 * i, 80, 30)
            Controls.Add(Button(i))
            AddHandler Button(i).MouseDown, AddressOf Mouse_Down
        Next
    End Sub
 
    Private Sub Mouse_Down(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.MouseEventArgs)
        Me.Text = DirectCast(sender, Control).Name
        Me.Controls(Me.Text).BackColor = Color.FromArgb(rnd.Next(256), rnd.Next( _
          256), rnd.Next(256))
    End Sub
 
    Private Sub Btn_MouseDown(sender As Object, e As _
      System.Windows.Forms.MouseEventArgs) Handles Btn.MouseDown
        For i As Int32 = 1 To 10
            Me.Controls.Find("Button" & i.ToString, True)(0).BackColor = _
              Color.FromArgb(rnd.Next(256), rnd.Next(256), rnd.Next(256))
        Next
    End Sub
End Class