oxyplot · tangmanger · Nov 13, 2025 · Nov 13, 2025 · Nov 13, 2025 · Jan 16, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -6,9 +6,13 @@ All notable changes to this project will be documented in this file.
 ### Added
 
 - Example to demonstrate how to create vertical BarSeries
-
+- Example to demonstrate how to create ErrorBarSeries Marker
+- Example to demonstrate how to create ErrorBarItem Spacing
+- 
 ### Fixed
 - DateTimeAxis converting local time rather than UTC to TimeZone
+- ErrorBarItem add marker
+- ErrorBarItem add spacing
 
 ## [2.2.0] - 2024-09-03
 

diff --git a/CONTRIBUTORS b/CONTRIBUTORS
@@ -156,3 +156,4 @@ Dmytro Shaurin
 Rustam Sayfutdinov
 Konstantin Stukov <havendv@gmail.com>
 jorgectf
+tangmanger <tangmanger@163.com>
diff --git a/Source/Examples/ExampleLibrary/Series/ErrorBarSeriesExamples.cs b/Source/Examples/ExampleLibrary/Series/ErrorBarSeriesExamples.cs
@@ -10,6 +10,8 @@ namespace ExampleLibrary
     using OxyPlot.Axes;
     using OxyPlot.Series;
     using OxyPlot.Legends;
+    using OxyPlot.Series;
+    using System;
 
     [Examples("ErrorBarSeries"), Tags("Series")]
     public class ErrorBarSeriesExamples
@@ -34,7 +36,7 @@ public static PlotModel GetErrorBarSeries()
             model.Legends.Add(l);
 
             var s1 = new ErrorBarSeries { Title = "Series 1", IsStacked = false, StrokeColor = OxyColors.Black, StrokeThickness = 1 };
-            s1.Items.Add(new ErrorBarItem { Value = 25, Error = 2 });
+            s1.Items.Add(new ErrorBarItem { Value = 35, Error = 2 });
             s1.Items.Add(new ErrorBarItem { Value = 137, Error = 25 });
             s1.Items.Add(new ErrorBarItem { Value = 18, Error = 4 });
             s1.Items.Add(new ErrorBarItem { Value = 40, Error = 29 });
@@ -72,5 +74,215 @@ public static PlotModel GetErrorBarSeriesThickErrorLines()
 
             return model;
         }
+
+        [Example("ErrorBarItemSpacing")]
+        public static PlotModel GetErrorBarSpacingSeries()
+        {
+            var model = new PlotModel
+            {
+                Title = "ErrorBarItemSpacing"
+            };
+
+            var l = new Legend
+            {
+                LegendPlacement = LegendPlacement.Outside,
+                LegendPosition = LegendPosition.BottomCenter,
+                LegendOrientation = LegendOrientation.Horizontal,
+                LegendBorderThickness = 0
+            };
+
+            model.Legends.Add(l);
+
+            var s1 = new ErrorBarSeries { Title = "Series 1", IsStacked = false, StrokeColor = OxyColors.Black, StrokeThickness = 1 };
+            s1.Items.Add(new ErrorBarItem { Spacing = 10, Value = 35, Error = 2 });
+            s1.Items.Add(new ErrorBarItem { Spacing = 20, Value = 137, Error = 25 });
+            s1.Items.Add(new ErrorBarItem { Spacing = 30, Value = 18, Error = 4 });
+            s1.Items.Add(new ErrorBarItem { Spacing = 40, Value = 40, Error = 29 });
+
+            var s2 = new ErrorBarSeries { Title = "Series 2", IsStacked = false, StrokeColor = OxyColors.Black, StrokeThickness = 1 };
+            s2.Items.Add(new ErrorBarItem { Value = 35, Error = 20 });
+            s2.Items.Add(new ErrorBarItem { Value = 17, Error = 7 });
+            s2.Items.Add(new ErrorBarItem { Value = 118, Error = 44 });
+            s2.Items.Add(new ErrorBarItem { Value = 49, Error = 29 });
+
+            var categoryAxis = new CategoryAxis { Position = AxisPosition.Left };
+            categoryAxis.Labels.Add("Category A");
+            categoryAxis.Labels.Add("Category B");
+            categoryAxis.Labels.Add("Category C");
+            categoryAxis.Labels.Add("Category D");
+
+            var valueAxis = new LinearAxis { Position = AxisPosition.Bottom, MinimumPadding = 0, MaximumPadding = 0.06, AbsoluteMinimum = 0 };
+            model.Series.Add(s1);
+            model.Series.Add(s2);
+            model.Axes.Add(categoryAxis);
+            model.Axes.Add(valueAxis);
+
+            return model;
+        }
+        [Example("MarkerErrorBarSeries")]
+        [DocumentationExample("Series/MarkerErrorBarSeries")]
+        public static PlotModel GetMarkerErrorBarSeries()
+        {
+            var model = new PlotModel
+            {
+                Title = "MarkerErrorBarSeries"
+            };
+            var l = new Legend
+            {
+                LegendPlacement = LegendPlacement.Outside,
+                LegendPosition = LegendPosition.BottomCenter,
+                LegendOrientation = LegendOrientation.Horizontal,
+                LegendBorderThickness = 0
+            };
+
+            model.Legends.Add(l);
+
+            var s1 = new ErrorBarSeries { Title = "Series 1", IsStacked = false, StrokeColor = OxyColors.Black, StrokeThickness = 1 };
+            s1.Items.Add(new ErrorBarItem
+            {
+                Value = 25,
+                Error = 2,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.Red,
+                MarkerType = MarkerType.Star,
+                MarkerSize = 5,
+                MarkerOffset = new ScreenPoint(5, 0),
+                MarkerStrokeColor = OxyColors.Blue,
+                MarkerStrokeThickness = 1,
+            });
+            s1.Items.Add(new ErrorBarItem
+            {
+                Value = 137,
+                Error = 25,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.Yellow,
+                MarkerType = MarkerType.Cross,
+                MarkerSize = 5,
+                MarkerOffset = new ScreenPoint(0, 0),
+                MarkerStrokeColor = OxyColors.Red,
+                MarkerStrokeThickness = 1,
+            });
+            s1.Items.Add(new ErrorBarItem
+            {
+                Value = 18,
+                Error = 4,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.Yellow,
+                MarkerType = MarkerType.Diamond,
+                MarkerSize = 8,
+                MarkerOffset = new ScreenPoint(0, 0),
+                MarkerStrokeColor = OxyColors.LightGreen,
+                MarkerStrokeThickness = 1,
+            });
+            s1.Items.Add(new ErrorBarItem
+            {
+                Value = 40,
+                Error = 29,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.Yellow,
+                MarkerType = MarkerType.Custom,
+                CustomOutline = GetSpiralStar(),
+                MarkerSize = 30,
+                MarkerOffset = new ScreenPoint(50, 0),
+                MarkerStrokeColor = OxyColors.LightGreen,
+                MarkerStrokeThickness = 1,
+            });
+
+            var s2 = new ErrorBarSeries { Title = "Series 2", IsStacked = false, StrokeColor = OxyColors.Black, StrokeThickness = 1 };
+            s2.Items.Add(new ErrorBarItem
+            {
+                Value = 25,
+                Error = 2,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.Red,
+                MarkerType = MarkerType.Square,
+                MarkerSize = 5,
+                MarkerOffset = new ScreenPoint(5, 0),
+                MarkerStrokeColor = OxyColors.Blue,
+                MarkerStrokeThickness = 1,
+            });
+            s2.Items.Add(new ErrorBarItem
+            {
+                Value = 137,
+                Error = 25,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.Yellow,
+                MarkerType = MarkerType.Triangle,
+                MarkerSize = 5,
+                MarkerOffset = new ScreenPoint(0, 0),
+                MarkerStrokeColor = OxyColors.Red,
+                MarkerStrokeThickness = 1,
+            });
+            s2.Items.Add(new ErrorBarItem
+            {
+                Value = 18,
+                Error = 4,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.Yellow,
+                MarkerType = MarkerType.Plus,
+                MarkerSize = 8,
+                MarkerOffset = new ScreenPoint(0, 0),
+                MarkerStrokeColor = OxyColors.LightGreen,
+                MarkerStrokeThickness = 1,
+            });
+            s2.Items.Add(new ErrorBarItem
+            {
+                Value = 40,
+                Error = 29,
+                IsMarkerVisible = true,
+                MarkerColor = OxyColors.GreenYellow,
+                MarkerType = MarkerType.Custom,
+                CustomOutline = GetHeartbeat(),
+                MarkerSize = 30,
+                MarkerOffset = new ScreenPoint(50, 0),
+                MarkerStrokeColor = OxyColors.BlueViolet,
+                MarkerStrokeThickness = 1,
+            });
+
+            var categoryAxis = new CategoryAxis { Position = AxisPosition.Left };
+            categoryAxis.Labels.Add("Category A");
+            categoryAxis.Labels.Add("Category B");
+            categoryAxis.Labels.Add("Category C");
+            categoryAxis.Labels.Add("Category D");
+
+            var valueAxis = new LinearAxis { Position = AxisPosition.Bottom, MinimumPadding = 0, MaximumPadding = 0.06, AbsoluteMinimum = 0 };
+            model.Series.Add(s1);
+            model.Series.Add(s2);
+            model.Axes.Add(categoryAxis);
+            model.Axes.Add(valueAxis);
+
+            return model;
+        }
+        public static ScreenPoint[] GetHeartbeat(int points = 20)
+        {
+            var outline = new ScreenPoint[points];
+            for (int i = 0; i < points; i++)
+            {
+                double x = 2.0 * i / (points - 1) - 1; 
+                double y = Math.Sin(x * Math.PI * 3) * Math.Exp(-Math.Abs(x)) * 0.8;
+
+                // Add some random pulse effects
+                y += Math.Sin(x * Math.PI * 8) * 0.1 * Math.Exp(-x * x * 4);
+
+                outline[i] = new ScreenPoint(x, y);
+            }
+            return outline;
+        }
+        public static ScreenPoint[] GetSpiralStar(int points = 24, double tightness = 0.1)
+        {
+            var outline = new ScreenPoint[points];
+            for (int i = 0; i < points; i++)
+            {
+                double progress = (double)i / points;
+                double radius = 0.2 + 0.8 * progress; 
+                double angle = 2 * Math.PI * (5 * progress + tightness * i);
+
+                outline[i] = new ScreenPoint(
+                    Math.Cos(angle) * radius,
+                    Math.Sin(angle) * radius
+                );
+            }
+            return outline;
+        }
     }
 }
diff --git a/Source/OxyPlot/Series/BarSeries/ErrorBarItem.cs b/Source/OxyPlot/Series/BarSeries/ErrorBarItem.cs
@@ -41,6 +41,47 @@ public ErrorBarItem(double value, double error, int categoryIndex = -1)
         /// </summary>
         public double Error { get; set; }
 
+        /// <summary>
+        /// Gets or sets the color of marker
+        /// </summary>
+        public OxyColor MarkerColor { get; set; }
+
+
+        /// <summary>
+        /// Gets or sets the marker Type
+        /// </summary>
+        public MarkerType MarkerType { get; set; }
+
+        /// <summary>
+        /// Gets or sets a custom polygon outline for the point marker. 
+        /// </summary>
+        public ScreenPoint[] CustomOutline { get; set; }
+
+        /// <summary>
+        /// Gets or sets the marker size
+        /// </summary>
+        public int MarkerSize { get; set; }
+
+        /// <summary>
+        /// Gets or sets the marker visible
+        /// </summary>
+        public bool IsMarkerVisible { get; set; }
+
+        /// <summary>
+        /// Gets or sets the marker offset
+        /// </summary>
+        public ScreenPoint MarkerOffset { get; set; }
+
+        /// <summary>
+        /// Gets or sets the marker stroke color
+        /// </summary>
+        public OxyColor MarkerStrokeColor { get; set; }
+
+        /// <summary>
+        /// Gets or sets the marker stroke thickness
+        /// </summary>
+        public double MarkerStrokeThickness { get; set; }
+
         /// <summary>
         /// Returns c# code that generates this instance.
         /// </summary>
@@ -61,5 +102,10 @@ public override string ToCode()
 
             return CodeGenerator.FormatConstructor(this.GetType(), "{0},{1}", this.Value, this.Error);
         }
+        /// <summary>
+        /// Bar spacing: the gap between adjacent bars
+        /// </summary>
+        public double Spacing { get; set; }
+
     }
 }