Public Class Form1
    Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.MouseEventArgs) Handles Me.MouseDown
        Dim pt As Point = Control.MousePosition
        Using Bmp As New Bitmap(1, 1), G As Graphics = Graphics.FromImage(Bmp)
            G.CopyFromScreen(pt.X, pt.Y, 0, 0, Bmp.Size)
            Dim c As Color = Bmp.GetPixel(0, 0)
            Me.Text = c.R.ToString & "," & c.G.ToString & "," & c.B.ToString
        End Using
    End Sub
 
    Private Sub Form1_Paint(ByVal sender As Object, ByVal e As _
      System.Windows.Forms.PaintEventArgs) Handles Me.Paint
        Using p As New Pen(Color.Black, 3)
            e.Graphics.DrawLine(p, 50, 150, 250, 150)
            e.Graphics.DrawLine(p, 150, 50, 150, 250)
        End Using
    End Sub
End Class