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XP.ImageProcessing.RoiControl/Models/AngleGroup.cs

@@ -19,6 +19,7 @@ namespace XP.ImageProcessing.RoiControl.Models
         public Point V { get; set; }
         public Point A { get; set; }
         public Point B { get; set; }
+        public int Index { get; set; }
 
         public double AngleDeg
         {
@@ -77,7 +78,7 @@ namespace XP.ImageProcessing.RoiControl.Models
                 midAngle += Math.PI;
 
             double labelDist = arcRadius + 16;
-            Label.Text = $"{angleDeg:F1}°";
+            Label.Text = (Index > 0 ? $"#{Index} " : "") + $"{angleDeg:F1}°";
             Canvas.SetLeft(Label, V.X + labelDist * Math.Cos(midAngle) - 15);
             Canvas.SetTop(Label, V.Y + labelDist * Math.Sin(midAngle) - 8);
             Label.Visibility = Visibility.Visible;