Subroutine DrawGradientSample draws the LinearGradientMode's name and a rectangle filled with that style.

Private Sub Form1_Paint(ByVal sender As Object, ByVal e As _
    System.Windows.Forms.PaintEventArgs) Handles _
    MyBase.Paint
    ' Currently the linear gradient modes have values 0 to
    ' 3.
    Const MIN_MODE As Integer = 0
    Const MAX_MODE As Integer = 3
    Dim x As Integer = 10
    Dim y As Integer = 10

    For i As Integer = MIN_MODE To MAX_MODE
        DrawGradientSample(e.Graphics, x, y, CType(i, _
            LinearGradientMode))
    Next i
End Sub

Private Sub DrawGradientSample(ByVal gr As Graphics, ByRef _
    x As Integer, ByRef y As Integer, ByVal gradient_mode _
    As LinearGradientMode)
    Const TEXT_WID As Integer = 155
    Const RECT_WID As Integer = 100
    Const RECT_HGT As Integer = 100
    Dim rect As New Rectangle( _
        x + TEXT_WID, y, RECT_WID, RECT_HGT)
    Dim br As New LinearGradientBrush( _
        rect, Color.Blue, Color.Red, gradient_mode)
    gr.DrawString( _
        gradient_mode.ToString & " (" & CInt(gradient_mode) _
            & ")", _
        Me.Font, Brushes.Black, x, y)
    gr.FillRectangle(br, rect)
    gr.DrawRectangle(Pens.Black, rect)

    y += RECT_HGT + 10
    If y + RECT_HGT > Me.ClientSize.Height Then
        x += TEXT_WID + RECT_WID + 30
        y = 10
    End If
End Sub