StreamGeometryContext.LineTo(Point, Boolean, Boolean) Method

Reference

Definition

Namespace:: System.Windows.Media

Assembly:: PresentationCore.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Draws a straight line to the specified Point.

public:
 abstract void LineTo(System::Windows::Point point, bool isStroked, bool isSmoothJoin);

public abstract void LineTo (System.Windows.Point point, bool isStroked, bool isSmoothJoin);

abstract member LineTo : System.Windows.Point * bool * bool -> unit

Public MustOverride Sub LineTo (point As Point, isStroked As Boolean, isSmoothJoin As Boolean)

Parameters

point: Point

The destination point for the end of the line.

isStroked: Boolean

true to make the segment stroked when a Pen is used to render the segment; otherwise, false.

isSmoothJoin: Boolean

true to treat the join between this segment and the previous segment as a corner when stroked with a Pen; otherwise, false.

Exceptions

InvalidOperationException

An attempt was made to add a segment without starting a figure by calling the BeginFigure(Point, Boolean, Boolean) method.

Examples

The following example shows how to draw a triangle using the LineTo method.

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;

namespace SDKSample
{
    // Use StreamGeometry with StreamGeometryContext to define a triangle shape.
    public partial class StreamGeometryTriangleExample : Page
    {
        public StreamGeometryTriangleExample()
        {
            // Create a path to draw a geometry with.
            Path myPath = new Path();
            myPath.Stroke = Brushes.Black;
            myPath.StrokeThickness = 1;

            // Create a StreamGeometry to use to specify myPath.
            StreamGeometry geometry = new StreamGeometry();
            geometry.FillRule = FillRule.EvenOdd;

            // Open a StreamGeometryContext that can be used to describe this StreamGeometry 
            // object's contents.
            using (StreamGeometryContext ctx = geometry.Open())
            {
                
                // Begin the triangle at the point specified. Notice that the shape is set to 
                // be closed so only two lines need to be specified below to make the triangle.
                ctx.BeginFigure(new Point(10, 100), true /* is filled */, true /* is closed */);

                // Draw a line to the next specified point.
                ctx.LineTo(new Point(100, 100), true /* is stroked */, false /* is smooth join */);

                // Draw another line to the next specified point.
                ctx.LineTo(new Point(100, 50), true /* is stroked */, false /* is smooth join */);
            }

            // Freeze the geometry (make it unmodifiable)
            // for additional performance benefits.
            geometry.Freeze();

            // Specify the shape (triangle) of the Path using the StreamGeometry.
            myPath.Data = geometry;

            // Add path shape to the UI.
            StackPanel mainPanel = new StackPanel();
            mainPanel.Children.Add(myPath);
            this.Content = mainPanel;
        }
    }
}


Imports System.Windows
Imports System.Windows.Controls
Imports System.Windows.Media
Imports System.Windows.Shapes

Namespace SDKSample
    ' Use StreamGeometry with StreamGeometryContext to define a triangle shape.
    Partial Public Class StreamGeometryTriangleExample
        Inherits Page
        Public Sub New()
            ' Create a path to draw a geometry with.
            Dim myPath As New Path()
            myPath.Stroke = Brushes.Black
            myPath.StrokeThickness = 1

            ' Create a StreamGeometry to use to specify myPath.
            Dim geometry As New StreamGeometry()
            geometry.FillRule = FillRule.EvenOdd

            ' Open a StreamGeometryContext that can be used to describe this StreamGeometry 
            ' object's contents.
            Using ctx As StreamGeometryContext = geometry.Open()

                ' Begin the triangle at the point specified. Notice that the shape is set to 
                ' be closed so only two lines need to be specified below to make the triangle.
                ctx.BeginFigure(New Point(10, 100), True, True) ' is closed  -  is filled 

                ' Draw a line to the next specified point.
                ctx.LineTo(New Point(100, 100), True, False) ' is smooth join  -  is stroked 

                ' Draw another line to the next specified point.
                ctx.LineTo(New Point(100, 50), True, False) ' is smooth join  -  is stroked 
            End Using

            ' Freeze the geometry (make it unmodifiable)
            ' for additional performance benefits.
            geometry.Freeze()

            ' Specify the shape (triangle) of the Path using the StreamGeometry.
            myPath.Data = geometry

            ' Add path shape to the UI.
            Dim mainPanel As New StackPanel()
            mainPanel.Children.Add(myPath)
            Me.Content = mainPanel
        End Sub
    End Class
End Namespace

Remarks

This method uses the end point of the previous segment as its starting point. If this is the first segment in a figure, it uses the point specified by the BeginFigure method as its start point.

A StreamGeometry cannot be serialized if it contains a Transform or any non-stroked or unfilled segments.

Applies to

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