1047330: Fixed chart accessibility, b-unit, leak issues.

src/Components/Charts/Chart/Annotations/ChartAnnotations.cs

@@ -1,5 +1,6 @@
 using System.ComponentModel;
 using Microsoft.AspNetCore.Components;
+using Syncfusion.Blazor.Toolkit.Charts.Internal;
 
 namespace Syncfusion.Blazor.Toolkit.Charts
 {
@@ -38,9 +39,23 @@ public class ChartAnnotations : ChartSubComponent, ISubcomponentTracker
         /// </value>
         /// <remarks>
         /// Use this property to provide an accessibility role for the <see cref="ChartAnnotations"/>.
+        /// The value, if non-empty, must be a valid WAI-ARIA role (for example
+        /// <c>"region"</c>, <c>"status"</c>, <c>"group"</c>). Invalid values are
+        /// rejected at component initialization to prevent invalid <c>role</c>
+        /// attributes from reaching the DOM.
         /// </remarks>
         [Parameter]
-        public string AccessibilityRole { get; set; } = string.Empty;
+        public string AccessibilityRole
+        {
+            get => _accessibilityRole;
+            set
+            {
+                DataVizCommonHelper.AriaRoleValidator.EnsureValidRole(value, nameof(AccessibilityRole));
+                _accessibilityRole = value;
+            }
+        }
+
+        private string _accessibilityRole = string.Empty;
 
         /// <summary>
         /// Gets or sets the accessibility keyboard navigation focus option for the <see cref="ChartAnnotations"/>.
@@ -253,4 +268,4 @@ public override void AddRenderer(IChartElementRenderer renderer)
         }
         #endregion
     }
-}
+}

src/Components/Charts/Chart/ChartArea/ChartSubTitleStyle.cs

@@ -115,6 +115,10 @@ public class ChartSubTitleStyle : ChartDefaultFont
         /// </value>
         /// <remarks>
         /// Use this property to provide an accessibility role for the chart subtitle.
+        /// The value, if non-empty, must be a valid WAI-ARIA role (for example
+        /// <c>"heading"</c>, <c>"region"</c>). Invalid values are rejected at
+        /// component initialization to prevent invalid <c>role</c> attributes from
+        /// reaching the DOM.
         /// </remarks>
         /// <example>
         /// <code>
@@ -127,7 +131,17 @@ public class ChartSubTitleStyle : ChartDefaultFont
         /// </code>
         /// </example>
         [Parameter]
-        public string AccessibilityRole { get; set; } = string.Empty;
+        public string AccessibilityRole
+        {
+            get => _accessibilityRole;
+            set
+            {
+                DataVizCommonHelper.AriaRoleValidator.EnsureValidRole(value, nameof(AccessibilityRole));
+                _accessibilityRole = value;
+            }
+        }
+
+        private string _accessibilityRole = string.Empty;
 
         /// <summary>
         /// Gets or sets the accessibility keyboard navigation focus option for the chart subtitle.

src/Components/Charts/Chart/ChartArea/ChartTitleStyle.cs

@@ -207,6 +207,10 @@ public class ChartTitleStyle : ChartDefaultFont
         /// </value>
         /// <remarks>
         /// Use this property to provide an accessibility role for the chart title.
+        /// The value, if non-empty, must be a valid WAI-ARIA role (for example
+        /// <c>"heading"</c>, <c>"region"</c>). Invalid values are rejected at
+        /// component initialization to prevent invalid <c>role</c> attributes from
+        /// reaching the DOM.
         /// </remarks>
         /// <example>
         /// <code>
@@ -219,7 +223,17 @@ public class ChartTitleStyle : ChartDefaultFont
         /// </code>
         /// </example>
         [Parameter]
-        public string AccessibilityRole { get; set; } = string.Empty;
+        public string AccessibilityRole
+        {
+            get => _accessibilityRole;
+            set
+            {
+                DataVizCommonHelper.AriaRoleValidator.EnsureValidRole(value, nameof(AccessibilityRole));
+                _accessibilityRole = value;
+            }
+        }
+
+        private string _accessibilityRole = string.Empty;
 
         /// <summary>
         /// Gets or sets the accessibility keyboard navigation focus option for the chart title.

src/Components/Charts/Chart/Legend/LegendSettings.cs

@@ -1,6 +1,6 @@
-using Microsoft.AspNetCore.Components;
+using System.ComponentModel;
+using Microsoft.AspNetCore.Components;
 using Syncfusion.Blazor.Toolkit.Charts.Internal;
-using System.ComponentModel;
 
 namespace Syncfusion.Blazor.Toolkit.Charts
 {
@@ -250,6 +250,10 @@ public string Height
         /// </value>
         /// <remarks>
         /// Use this property to provide an accessibility role for the <see cref="ChartLegendSettings"/>.
+        /// The value, if non-empty, must be a valid WAI-ARIA role (for example
+        /// <c>"region"</c>, <c>"group"</c>, <c>"list"</c>). Invalid values are
+        /// rejected at component initialization to prevent invalid <c>role</c>
+        /// attributes from reaching the DOM.
         /// </remarks>
         /// <example>
         /// <code>
@@ -265,7 +269,17 @@ public string Height
         /// </code>
         /// </example>
         [Parameter]
-        public string AccessibilityRole { get; set; } = string.Empty;
+        public string AccessibilityRole
+        {
+            get => _accessibilityRole;
+            set
+            {
+                DataVizCommonHelper.AriaRoleValidator.EnsureValidRole(value, nameof(AccessibilityRole));
+                _accessibilityRole = value;
+            }
+        }
+
+        private string _accessibilityRole = string.Empty;
 
         /// <summary>
         /// Gets or sets the accessibility keyboard navigation focus option for the <see cref="ChartLegendSettings"/>.

src/Components/Charts/Chart/Renderer/AxisRenderer/ChartAxisRenderer.cs

@@ -1820,7 +1820,7 @@ internal void CustomizeGridRenderingOptions(string key)
                         foreach (PathOptions option in axisGridOptions)
                         {
                             option.Stroke = Axis?.MajorGridLines.Color ?? string.Empty;
-                            option.StrokeWidth = Axis?.Renderer?.MajorGridLinesWidth ?? 0;
+                            option.StrokeWidth = Axis?.MajorGridLines.Width ?? 0;
                             option.StrokeDashArray = Axis?.MajorGridLines.DashArray ?? string.Empty;
                         }
                     }
@@ -1829,7 +1829,7 @@ internal void CustomizeGridRenderingOptions(string key)
                         foreach (CircleOptions option in AxisRenderInfo.MajorGridCircleOptions)
                         {
                             option.Stroke = Axis?.MajorGridLines.Color ?? string.Empty;
-                            option.StrokeWidth = Axis?.Renderer?.MajorGridLinesWidth ?? 0;
+                            option.StrokeWidth = Axis?.MajorGridLines.Width ?? 0;
                             option.StrokeDashArray = Axis?.MajorGridLines.DashArray ?? string.Empty;
                         }
                     }

src/Components/Charts/Chart/Series/ChartSeries.cs

@@ -1,11 +1,11 @@
-using Microsoft.AspNetCore.Components;
-using Syncfusion.Blazor.Toolkit.Charts.Internal;
-using Syncfusion.Blazor.Toolkit.Data;
-using Syncfusion.Blazor.Toolkit.Internal;
 using System.Collections.Generic;
 using System.Collections.Specialized;
 using System.ComponentModel;
 using System.Globalization;
+using Microsoft.AspNetCore.Components;
+using Syncfusion.Blazor.Toolkit.Charts.Internal;
+using Syncfusion.Blazor.Toolkit.Data;
+using Syncfusion.Blazor.Toolkit.Internal;
 
 namespace Syncfusion.Blazor.Toolkit.Charts
 {
@@ -328,6 +328,10 @@ public double Width
         /// <value>A string that defines the accessibility role for the <see cref="ChartSeries"/>.</value>
         /// <remarks>
         /// Use this property to specify the accessibility role for the <see cref="ChartSeries"/> root element.
+        /// The value, if non-empty, must be a valid WAI-ARIA role (for example
+        /// <c>"region"</c>, <c>"img"</c>, <c>"list"</c>). Invalid values are
+        /// rejected at component initialization to prevent invalid <c>role</c>
+        /// attributes from reaching the DOM.
         /// </remarks>
         /// <example>
         /// <code>
@@ -340,7 +344,17 @@ public double Width
         /// </code>
         /// </example>
         [Parameter]
-        public string AccessibilityRole { get; set; } = string.Empty;
+        public string AccessibilityRole
+        {
+            get => _accessibilityRole;
+            set
+            {
+                DataVizCommonHelper.AriaRoleValidator.EnsureValidRole(value, nameof(AccessibilityRole));
+                _accessibilityRole = value;
+            }
+        }
+
+        private string _accessibilityRole = string.Empty;
 
         /// <summary>
         /// Gets or sets a value indicating whether the series root can receive keyboard focus.

src/Components/Charts/Chart/Series/Trendline/ChartTrendline.cs

@@ -258,7 +258,13 @@ public TrendlineTypes Type
         /// <summary>
         /// Gets or sets the ARIA role for the trendline.
         /// </summary>
-        /// <value>A string representing the ARIA role. Default is empty.</value>
+        /// <value> A string representing the ARIA role. Default is empty.</value>
+        /// <remarks>
+        /// The value, if non-empty, must be a valid WAI-ARIA role (for example
+        /// <c>"region"</c>, <c>"group"</c>). Invalid values are rejected at
+        /// component initialization to prevent invalid <c>role</c> attributes from
+        /// reaching the DOM.
+        /// </remarks>
         /// <example>
         /// <code>
         /// <![CDATA[
@@ -274,7 +280,17 @@ public TrendlineTypes Type
         /// </code>
         /// </example>
         [Parameter]
-        public string AccessibilityRole { get; set; } = string.Empty;
+        public string AccessibilityRole
+        {
+            get => _accessibilityRole;
+            set
+            {
+                DataVizCommonHelper.AriaRoleValidator.EnsureValidRole(value, nameof(AccessibilityRole));
+                _accessibilityRole = value;
+            }
+        }
+
+        private string _accessibilityRole = string.Empty;
 
         /// <summary>
         /// Gets or sets whether the trendline is focusable via keyboard navigation.

src/Components/Charts/Chart/SfChart.razor.LifeCycle.cs

@@ -1,7 +1,7 @@
-using Microsoft.JSInterop;
-using Syncfusion.Blazor.Toolkit.Charts.Internal;
-using System.Collections.Specialized;
+using System.Collections.Specialized;
 using System.ComponentModel;
+using Microsoft.JSInterop;
+using Syncfusion.Blazor.Toolkit.Charts.Internal;
 
 namespace Syncfusion.Blazor.Toolkit.Charts
 {
@@ -304,6 +304,12 @@ protected override async ValueTask DisposeAsyncCore()
                 _chartJsModule = null;
                 _chartJsInProcessModule = null;
             }
+
+            // Clear instance-level font measurement caches to prevent memory retention
+            // after the chart is disposed. This ensures per-circuit/per-chart isolation.
+            _fontSizeCache?.Clear();
+            _requestedFontKeys?.Clear();
+
             await base.DisposeAsyncCore().ConfigureAwait(true);
         }
 

src/Components/Charts/Chart/SfChart.razor.Members.cs

@@ -1,8 +1,8 @@
-using Microsoft.AspNetCore.Components;
-using Syncfusion.Blazor.Toolkit.Internal;
+using System.Collections.Specialized;
 using System.ComponentModel;
+using Microsoft.AspNetCore.Components;
 using Syncfusion.Blazor.Toolkit.Charts.Internal;
-using System.Collections.Specialized;
+using Syncfusion.Blazor.Toolkit.Internal;
 
 namespace Syncfusion.Blazor.Toolkit.Charts
 {
@@ -178,6 +178,10 @@ internal class ChartDataState
         /// </value>
         /// <remarks>
         /// Use this property to provide an accessibility role for the <see cref="SfChart">Chart</see> component.
+        /// The value, if non-empty, must be a valid WAI-ARIA role (for example
+        /// <c>"region"</c>, <c>"figure"</c>, <c>"img"</c>). Invalid values are
+        /// rejected at component initialization to prevent invalid <c>role</c>
+        /// attributes from reaching the DOM.
         /// </remarks>
         /// <example>
         /// <code>
@@ -189,7 +193,17 @@ internal class ChartDataState
         /// </code>
         /// </example>
         [Parameter]
-        public string AccessibilityRole { get; set; } = string.Empty;
+        public string AccessibilityRole
+        {
+            get => _accessibilityRole;
+            set
+            {
+                DataVizCommonHelper.AriaRoleValidator.EnsureValidRole(value, nameof(AccessibilityRole));
+                _accessibilityRole = value;
+            }
+        }
+
+        private string _accessibilityRole = string.Empty;
 
         /// <summary>
         /// Gets or sets the accessibility keyboard navigation focus option for the <see cref="SfChart">Chart</see> component.

src/Components/Charts/Chart/SfChart.razor.cs

@@ -1,15 +1,16 @@
-using Microsoft.AspNetCore.Components;
-using Microsoft.AspNetCore.Components.Rendering;
-using Microsoft.JSInterop;
-using Syncfusion.Blazor.Toolkit.Charts.Internal;
+using System.Collections.Concurrent;
+using System.ComponentModel;
 using System.Globalization;
+using System.Reflection;
+using System.Runtime.CompilerServices;
 using System.Text.Json;
 using System.Text.Json.Serialization;
-using System.Reflection;
-using System.ComponentModel;
-using Syncfusion.Blazor.Toolkit.Data;
+using Microsoft.AspNetCore.Components;
+using Microsoft.AspNetCore.Components.Rendering;
 using Microsoft.Extensions.Localization;
-using System.Runtime.CompilerServices;
+using Microsoft.JSInterop;
+using Syncfusion.Blazor.Toolkit.Charts.Internal;
+using Syncfusion.Blazor.Toolkit.Data;
 
 [assembly: InternalsVisibleTo("Syncfusion.Blazor.Toolkit.BUnitTest")]
 namespace Syncfusion.Blazor.Toolkit.Charts
@@ -178,6 +179,9 @@ internal class JsInteropState
         internal List<IChartEventBorder> _seriesBorders = [];
         internal List<IAxis> _axes = [];
         internal List<PatternOptions> _highLightPatternCollection = [];
+        // Instance-level font measurement caches
+        internal ConcurrentDictionary<string, Size> _fontSizeCache = new();
+        internal ConcurrentDictionary<string, byte> _requestedFontKeys = new();
         internal ChartAnnotations _annotations = new();
         internal DomRect _elementOffset = new();
         /*To store the SVGElement's dimensions value.*/
@@ -1244,9 +1248,9 @@ private async Task GetOtherLanguageCharSizeAsync(bool _updateDataSource)
         /// <param name="text">The text to analyze.</param>
         /// <param name="font">The font options for the text.</param>
         /// <param name="distinctKeys">The collection to populate with distinct character keys.</param>
-        private static void GetDistinctCharacter(string text, ChartFontOptions font, List<string> distinctKeys)
+        private void GetDistinctCharacter(string text, ChartFontOptions font, List<string> distinctKeys)
         {
-            ChartHelper.GetDistinctCharacter(text, font, distinctKeys);
+            ChartHelper.GetDistinctCharacter(text, font, distinctKeys, this);
         }
 
         /// <summary>
@@ -1271,7 +1275,7 @@ private async Task LoadCharacterDictionaryAsync(List<string> distinctKeys)
             Dictionary<string, SymbolLocation> charSizeList = JsonSerializer.Deserialize<Dictionary<string, SymbolLocation>>(result) ?? null!;
             foreach (KeyValuePair<string, SymbolLocation> charSize in charSizeList)
             {
-                _ = ChartHelper.SizePerCharacter.TryAdd(charSize.Key, new Size { Width = charSize.Value.X, Height = charSize.Value.Y });
+                _ = _fontSizeCache.TryAdd(charSize.Key, new Size { Width = charSize.Value.X, Height = charSize.Value.Y });
             }
         }
 
@@ -1832,10 +1836,9 @@ internal async Task GetCharSizeListAsync(List<string> fontKeys)
             List<string> uniqueKeys = [];
             foreach (string fontKey in fontKeys)
             {
-                if (!ChartHelper.ChartFontKeys.Contains(fontKey))
+                if (_requestedFontKeys.TryAdd(fontKey, 0))
                 {
                     uniqueKeys.Add(fontKey);
-                    ChartHelper.ChartFontKeys.Add(fontKey);
                 }
             }
 
@@ -1855,7 +1858,7 @@ internal async Task GetCharSizeListAsync(List<string> fontKeys)
             int i = 33, j = 0;
             foreach (string width in result_2)
             {
-                _ = ChartHelper.SizePerCharacter.TryAdd(Convert.ToChar(i) + Constants.Underscore + uniqueKeys[j], new Size { Width = Convert.ToInt16(width, null), Height = 133 });
+                _ = _fontSizeCache.TryAdd(Convert.ToChar(i) + Constants.Underscore + uniqueKeys[j], new Size { Width = Convert.ToInt16(width, null), Height = 133 });
                 i++;
                 if (i > 590)
                 {
@@ -2590,17 +2593,6 @@ protected override void OnParametersSet()
             PushSubcomponent();
         }
 
-        /// <summary>
-        /// Performs cleanup operations when the component is being disposed.
-        /// </summary>
-        /// <exclude />
-        [EditorBrowsable(EditorBrowsableState.Never)]
-        [Browsable(false)]
-        protected override ValueTask DisposeAsyncCore()
-        {
-            return base.DisposeAsyncCore();
-        }
-
         #endregion
 
         #region Protected Methods