Disegnare una linea Gradiente (da colore a colore)

Imports System.Drawing.Drawing2D

Public Class Form1
' Fill a rectangle with a linear gradient brush.

Private Sub Form1_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
' Draw with a horizontal gradient.

Dim rect1 As New Rectangle(20, 20, 250, 100)
Using br As New LinearGradientBrush( _
rect1, Color.Red, Color.Blue, LinearGradientMode.Horizontal)
e.Graphics.FillRectangle(br, rect1)
e.Graphics.DrawRectangle(Pens.Black, rect1)
End Using

'' Draw with a horizontal gradient.

'Dim rect2 As New Rectangle(20, 140, 250, 100)

'Using br As New LinearGradientBrush( _

' rect2, Color.Red, Color.Blue, LinearGradientMode.Horizontal)

' ' Define a rainbow blend.

' Dim color_blend As New ColorBlend()

' color_blend.Colors = New Color() _

' {Color.Red, Color.Orange, Color.Yellow, _

' Color.Lime, Color.Blue, Color.Indigo, Color.DarkViolet}

' color_blend.Positions = New Single() _

' {0 / 6, 1 / 6, 2 / 6, 3 / 6, 4 / 6, 5 / 6, 6 / 6}

' br.InterpolationColors = color_blend


' ' Fill a rectangle with the blended brush.

' e.Graphics.FillRectangle(br, rect2)

' e.Graphics.DrawRectangle(Pens.Black, rect2)

'End Using

End Sub
End Class