准备区分节点、参数、返回值的连接，做个备份

Workbench/Node/Junction/JunctionData.cs

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+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.Shapes;
+
+namespace Serein.Workbench.Node.View
+{
+
+    #region Model，不科学的全局变量
+    public class MyLine
+    {
+        public MyLine(Canvas canvas, Line line)
+        {
+            Canvas = canvas;
+            VirtualLine = line;
+            canvas?.Children.Add(line);
+        }
+
+        public Canvas Canvas { get; set; }
+        public Line VirtualLine { get; set; }
+
+        public void Remove()
+        {
+            Canvas?.Children.Remove(VirtualLine);
+        }
+    }
+
+    public class ConnectingData
+    {
+        public JunctionControlBase StartJunction { get; set; }
+        public JunctionControlBase ChangingJunction { get; set; }
+        public Point StartPoint { get; set; }
+        public MyLine VirtualLine { get; set; }
+    }
+
+    public static class GlobalJunctionData
+    {
+        private static ConnectingData? myGlobalData;
+
+        public static ConnectingData? MyGlobalData
+        {
+            get => myGlobalData;
+            set
+            {
+                if (myGlobalData == null)
+                {
+                    myGlobalData = value;
+                }
+            }
+        }
+
+
+
+        public static bool IsCreatingConnection => myGlobalData is not null;
+
+        public static bool CanCreate => myGlobalData?.ChangingJunction.Equals(myGlobalData?.StartJunction) == false;
+
+        public static void OK()
+        {
+            myGlobalData?.VirtualLine.Remove();
+            myGlobalData = null;
+        }
+    }
+    #endregion
+}