一个可拖拽的多点线段（usercontrol）

、

<UserControl x:Class="GmapUserControls.DragLine"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
             xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
             xmlns:local="clr-namespace:GmapUserControls"
             mc:Ignorable="d" 
             Focusable="True"
             d:DesignHeight="450" d:DesignWidth="800" Loaded="UserControl_Loaded" >
    <Canvas x:Name="canvas2">
        <Canvas.Resources>
            <ControlTemplate TargetType="Thumb" x:Key="markerTemplate">
                <Ellipse Fill="{TemplateBinding Background}" 
                             HorizontalAlignment="Stretch" 
                             VerticalAlignment="Stretch"/>
            </ControlTemplate>

            <Style TargetType="Thumb" x:Key="markerStyle">
                <Setter Property="Width" Value="10"/>
                <Setter Property="Height" Value="10" />
                <Setter Property="Visibility" Value="Hidden"/>
                <Setter Property="RenderTransform">
                    <Setter.Value>
                        <TranslateTransform X="-5" Y="-5" />
                    </Setter.Value>
                </Setter>
                <Setter Property="Cursor" Value="Hand"/>
                
                <Setter Property="Template" Value="{StaticResource markerTemplate}" />
                <EventSetter Event="DragDelta" Handler="Thumb_DragDelta"/>
                <Style.Triggers>
                    <DataTrigger Binding="{Binding Path=.}" Value="{x:Null}">
                        <Setter Property="Visibility" Value="Hidden" />
                    </DataTrigger>
                </Style.Triggers>
            </Style>
            <Style TargetType="{x:Type Line}">
                <Setter Property="Cursor" Value="Cross"/>
                <EventSetter Event="MouseLeftButtonDown" Handler="Line_MouseLeftButtonDown" />
                <EventSetter Event="MouseRightButtonDown" Handler="Line_MouseRightButtonDown"/>
            </Style>
        </Canvas.Resources>



        <Thumb x:Name="marker1" DataContext="{x:Null}"
                   Canvas.Left="{Binding Path=X1,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" 
                   Canvas.Top="{Binding Path=Y1,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" 
                   Background="Red"
            
                   Style="{StaticResource  markerStyle}" />

        <Thumb x:Name="marker2"
                   DataContext="{x:Null}"
                   Canvas.Left="{Binding Path=X2,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" 
                   Canvas.Top="{Binding Path=Y2,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" 
             
                   Background="Red" 
           Style="{StaticResource  markerStyle}" />
    </Canvas>
</UserControl>

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace GmapUserControls
{
    /// <summary>
    /// DragLine.xaml 的交互逻辑
    /// </summary>
    public partial class DragLine : UserControl
    {
        private List<Point> _points;

        public List<Point> DragPoints
        {
            get { return _points; }
            set { _points = value; }
        }
        private List<Line> _lines;
        public List<Line> DragLines
        {
            get { return _lines; }
        }
        //Line line;
        public DragLine()
        {
            InitializeComponent();
            _lines = new List<Line>();
        }
        private void UserControl_Loaded(object sender, RoutedEventArgs e)
        {
         
            Line line;
            for (int i = 0; i < _points.Count - 1; i++)
            {
                Ellipse ellipse1 = new Ellipse() { Width = 5, Height = 5, Fill = Brushes.Red, RenderTransform = new TranslateTransform(-2.5, -2.5) };
                Ellipse ellipse2 = new Ellipse() { Width = 5, Height = 5, Fill = Brushes.Red, RenderTransform = new TranslateTransform(-2.5, -2.5) };

                line = new Line() { StrokeThickness = 1, Stroke = Brushes.Red };


                line.X1 = _points[i].X;
                line.Y1 = _points[i].Y;
                line.X2 = _points[i + 1].X;
                line.Y2 = _points[i + 1].Y;


                ellipse1.SetBinding(Canvas.LeftProperty, new Binding("X1") { Source = line, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                ellipse1.SetBinding(Canvas.TopProperty, new Binding("Y1") { Source = line, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                ellipse2.SetBinding(Canvas.LeftProperty, new Binding("X2") { Source = line, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                ellipse2.SetBinding(Canvas.TopProperty, new Binding("Y2") { Source = line, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                var canvas = this.canvas2;

                canvas.Children.Insert(i, line);
                canvas.Children.Add(ellipse1);
                canvas.Children.Add(ellipse2);
                this.marker1.DataContext = line;
                this.marker2.DataContext = line;
                _lines.Add(line);

                for (int t = 0; t < _lines.Count - 1; t++)
                {

                    _lines[t].SetBinding(Line.X2Property, new Binding("X1") { Source = _lines[t + 1], Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                    _lines[t].SetBinding(Line.Y2Property, new Binding("Y1") { Source = _lines[t + 1], Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                }

               

            }




        }
        private void Thumb_DragDelta(object sender, System.Windows.Controls.Primitives.DragDeltaEventArgs e)
        {
            var thumb = (System.Windows.Controls.Primitives.Thumb)sender;
            Canvas.SetLeft(thumb, Canvas.GetLeft(thumb) + e.HorizontalChange);
            Canvas.SetTop(thumb, Canvas.GetTop(thumb) + e.VerticalChange);

        }
        private void Line_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            marker1.Visibility = Visibility.Visible;
            marker2.Visibility = Visibility.Visible;
            Line line = (Line)sender;

            int q = canvas2.Children.IndexOf(line);

            this.marker1.DataContext = line;
            this.marker2.DataContext = line;

            var p = e.GetPosition((Canvas)line.Parent);
            var p1 = new Point(line.X1, line.Y1);
            var p2 = new Point(line.X2, line.Y2);



            if ((Keyboard.Modifiers & ModifierKeys.Control) == ModifierKeys.Control)
            {


                Line newline = new Line();
                newline.Stroke = line.Stroke;
                newline.StrokeThickness = line.StrokeThickness;

                System.Windows.Controls.Primitives.Thumb thumb = null;
                string num = "";
                if ((p1 - p).Length < 20)
                {
                    newline.X2 = p1.X;
                    newline.Y2 = p1.Y;
                    num = "1";

                }
                else if ((p2 - p).Length < 20)
                {
                    newline.X2 = p2.X;
                    newline.Y2 = p2.Y;
                    num = "2";
                }
                else
                {
                    return;
                }

                newline.SetBinding(Line.X1Property, new Binding("X" + num) { Source = line, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                newline.SetBinding(Line.Y1Property, new Binding("Y" + num) { Source = line, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });

                var canvas = (Canvas)line.Parent;
                int index = canvas.Children.IndexOf(marker1);
                canvas.Children.Insert(index, newline);


                Ellipse ellipse1 = new Ellipse() { Width = 5, Height = 5, Fill = Brushes.Red, RenderTransform = new TranslateTransform() { X = -2, Y = -2 } };
                Ellipse ellipse2 = new Ellipse() { Width = 5, Height = 5, Fill = Brushes.Red, RenderTransform = new TranslateTransform() { X = -2, Y = -2 } };

                ellipse1.SetBinding(Canvas.LeftProperty, new Binding("X1") { Source = newline, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                ellipse1.SetBinding(Canvas.TopProperty, new Binding("Y1") { Source = newline, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                ellipse2.SetBinding(Canvas.LeftProperty, new Binding("X2") { Source = newline, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                ellipse2.SetBinding(Canvas.TopProperty, new Binding("Y2") { Source = newline, Mode = BindingMode.TwoWay, UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged });
                canvas.Children.Add(ellipse1);
                canvas.Children.Add(ellipse2);


                _lines.Add(newline);
                this.marker1.DataContext = newline;
                this.marker2.DataContext = newline;

                Dispatcher.BeginInvoke(new Action(() => { marker2.RaiseEvent(e); }), System.Windows.Threading.DispatcherPriority.Render);

            }
        }



        private void Line_MouseRightButtonDown(object sender, MouseButtonEventArgs e)
        {
            marker1.Visibility = Visibility.Hidden;
            marker2.Visibility = Visibility.Hidden;
        }

 
    }
}

后台wpf调用：

  dragLine = new DragLine();
            dragLine.DragPoints= new List<Point>()
            {
            new Point(400,10),
            new Point(90,180),
            new Point (100,130),
            new Point (170,200),
            new Point(300,80),
            new Point (150,300)
            };
            this.grid1.Children.Add(dragLine);