Graphics.DrawBeziers Method (Pen, PointF())


Draws a series of Bézier splines from an array of PointF structures.

Namespace:   System.Drawing
Assembly:  System.Drawing (in System.Drawing.dll)

Public Sub DrawBeziers (
	pen As Pen,
	points As PointF()


Type: System.Drawing.Pen

Pen that determines the color, width, and style of the curve.

Type: System.Drawing.PointF()

Array of PointF structures that represent the points that determine the curve. The number of points in the array should be a multiple of 3 plus 1, such as 4, 7, or 10.

Exception Condition

pen is null.


points is null.

The number of points in the array should be a multiple of 3 plus 1 because the first spline requires 4 points and any other splines require 3 points each. The first Bézier curve is drawn from the first point to the fourth point in the point array. The second and third points are control points that determine the shape of the curve. Each subsequent curve needs exactly three more points: two more control points and an ending point. The ending point of the previous curve is used as the starting point for each additional curve.

The following code example is designed for use with Windows Forms, and it requires PaintEventArgse, which is a parameter of the Paint event handler. The code performs the following actions:

  • Creates a black pen.

  • Creates the start, end, and two control points for a first curve and endpoint and two control points for a second curve.

  • Draws the successive Bézier curves to the screen.

Private Sub DrawBeziersPointF(ByVal e As PaintEventArgs)

    ' Create pen.
    Dim blackPen As New Pen(Color.Black, 3)

    ' Create points for curve.
    Dim start As New PointF(100.0F, 100.0F)
    Dim control1 As New PointF(200.0F, 10.0F)
    Dim control2 As New PointF(350.0F, 50.0F)
    Dim end1 As New PointF(500.0F, 100.0F)
    Dim control3 As New PointF(600.0F, 150.0F)
    Dim control4 As New PointF(650.0F, 250.0F)
    Dim end2 As New PointF(500.0F, 300.0F)
    Dim bezierPoints As PointF() = {start, control1, control2, _
    end1, control3, control4, end2}

    ' Draw arc to screen.
    e.Graphics.DrawBeziers(blackPen, bezierPoints)
End Sub

.NET Framework
Available since 1.1
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