Small performance update for rendering list items

.editorconfig

@@ -60,8 +60,8 @@ dotnet_style_parentheses_in_relational_binary_operators = always_for_clarity:err
 dotnet_style_require_accessibility_modifiers = for_non_interface_members:error
 
 # Require var all the time.
-csharp_style_var_for_built_in_types = true:error
-csharp_style_var_when_type_is_apparent = true:error
+csharp_style_var_for_built_in_types = true:suggestion
+csharp_style_var_when_type_is_apparent = true:suggestion
 csharp_style_var_elsewhere = true:suggestion
 
 # Expression-level preferences

examples/Demo/Shared/Pages/List/Select/Examples/SelectFromListOfOptions.razor

@@ -82,8 +82,8 @@
     List<Option<int>> intOptions = new()
     {
         { new Option<int> { Value = 1, Text = 1, Disabled = true, Icon = (new Icons.Regular.Size24.NumberCircle1(), Color.Neutral, "start" ) } },
-        { new Option<int> { Value = 2, Text = 2, Icon = (new Icons.Regular.Size24.NumberCircle2(), Color.Neutral, "start" ) } },
+        { new Option<int> { Value = 2, Text = 2, Icon = (new Icons.Regular.Size24.NumberCircle2(), Color.Neutral, "end" ) } },
         { new Option<int> { Value = 3, Text = 3, Icon = (new Icons.Regular.Size24.NumberCircle3(), Color.Neutral, "start" ) } }
 
     };
-}
+}

src/Core/Components/List/IOptionIcon.cs

@@ -0,0 +1,8 @@
+// ------------------------------------------------------------------------
+// MIT License - Copyright (c) Microsoft Corporation. All rights reserved.
+// ------------------------------------------------------------------------
+namespace Microsoft.FluentUI.AspNetCore.Components;
+internal interface IOptionIcon
+{
+    (Icon Value, Color? Color, string? Slot)? Icon { get; set; }
+}

src/Core/Components/List/ListComponentBase.razor

@@ -7,15 +7,19 @@
 
 @code
 {
+
     private void RenderOptions(RenderTreeBuilder __builder)
     {
+
         if (Items is null)
         {
             @ChildContent
         }
         else
         {
-            foreach (TOption item in Items)
+            bool optionItems = typeof(TOption).IsGenericType && typeof(TOption).GetGenericTypeDefinition() == typeof(Option<>);
+
+            @foreach (TOption item in Items)
             {
                 <FluentOption TOption="TOption"
                               Value="@GetOptionValue(item)"
@@ -30,26 +34,21 @@
                     {
                         @GetOptionText(item)
                     }
-
-                    @{
-                        Type t = item.GetType(); 
-
-                    }
-                    @if (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Option<>))
+
+                    @if (optionItems)
                     {
-                        PropertyInfo? prop = t.GetProperty("Icon");
-
-                        if (prop is not null)
+                        var optionIcon = (IOptionIcon)item;
+                        var value = optionIcon.Icon;
+
+                        if (value.HasValue)
                         {
-                            (Icon Value, Color? Color, string? Slot) = ((Icon Value, Color? Color, string? Slot)) prop.GetValue(item)!;
-                            if (Value != null)
-                            {
-                                <FluentIcon Value="@Value" Color="@Color" Slot="@Slot" />
-                            }
+                            var icon = value.Value;
+                            <FluentIcon Value="@icon.Value" Color="@icon.Color" Slot="@icon.Slot" />
                         }
-                    }                
+
+                    }
                 </FluentOption>
             }
         }
     }
-}
+}

src/Core/Components/List/ListComponentBase.razor.cs

@@ -534,7 +534,7 @@ protected virtual async Task OnKeydownHandlerAsync(KeyboardEventArgs e)
         // This delay is needed for WASM to be able to get the updated value of the active descendant.
         // Without it, the value sometimes lags behind and you then need two keypresses to move to the next/prev option.
         await Task.Delay(1);
-        string? id = await Module!.InvokeAsync<string>("getAriaActiveDescendant", Id);
+        var id = await Module!.InvokeAsync<string>("getAriaActiveDescendant", Id);
 
         FluentOption<TOption> item = _internalListContext.Options.First(i => i.Id == id);
 

src/Core/Components/List/Option.cs

@@ -1,12 +1,12 @@
 namespace Microsoft.FluentUI.AspNetCore.Components;
 
-public class Option<TType>
+public class Option<TType> : IOptionIcon
 {
     public TType? Value { get; set; }
 
     public TType? Text { get; set; }
 
-    public (Icon Value, Color? Color, string? Slot) Icon { get; set; }
+    public (Icon Value, Color? Color, string? Slot)? Icon { get; set; }
 
     public bool Disabled { get; set; } = false;
 

tests/TemplateValidation/NoAuthentication/B-Server/Global/Components/Pages/Home.razor

@@ -4,4 +4,4 @@
 
 <h1>Hello, world!</h1>
 
-Welcome to your new Fluent Blazor app.
+Welcome to your new Fluent Blazor app.

tests/TemplateValidation/NoAuthentication/B-Server/Global/FluentUI.TemplateValidation.csproj

@@ -7,7 +7,10 @@
   </PropertyGroup>
 
   <ItemGroup>
-	<PackageReference Include="Microsoft.FluentUI.AspNetCore.Components" Version="4.*-* " />
-    <PackageReference Include="Microsoft.FluentUI.AspNetCore.Components.Icons" Version="4.*-* " />
+	    <PackageReference Include="Microsoft.FluentUI.AspNetCore.Components.Icons" Version="4.*-* " />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\..\..\..\..\src\Core\Microsoft.FluentUI.AspNetCore.Components.csproj" />
   </ItemGroup>
 </Project>