.Net: Extend plugins sample to demonstrate the use of enums (#5850)

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- [ ] The PR follows the [SK Contribution
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dotnet/Directory.Packages.props

@@ -6,7 +6,7 @@
   </PropertyGroup>
   <ItemGroup>
     <PackageVersion Include="Azure.AI.OpenAI" Version="1.0.0-beta.15" />
-    <PackageVersion Include="Azure.Identity" Version="1.10.4" />
+    <PackageVersion Include="Azure.Identity" Version="1.11.0" />
     <PackageVersion Include="Azure.Monitor.OpenTelemetry.Exporter" Version="1.2.0" />
     <PackageVersion Include="Azure.Search.Documents" Version="11.5.1" />
     <PackageVersion Include="Handlebars.Net.Helpers" Version="2.4.1.5" />

dotnet/samples/KernelSyntaxExamples/Getting_Started/Step2_Add_Plugins.cs

@@ -2,6 +2,7 @@
 
 using System;
 using System.ComponentModel;
+using System.Text.Json.Serialization;
 using System.Threading.Tasks;
 using Examples;
 using Microsoft.SemanticKernel;
@@ -28,6 +29,7 @@ public async Task RunAsync()
                 modelId: TestConfiguration.OpenAI.ChatModelId,
                 apiKey: TestConfiguration.OpenAI.ApiKey);
         kernelBuilder.Plugins.AddFromType<TimeInformation>();
+        kernelBuilder.Plugins.AddFromType<WidgetFactory>();
         Kernel kernel = kernelBuilder.Build();
 
         // Example 1. Invoke the kernel with a prompt that asks the AI for information it cannot provide and may hallucinate
@@ -39,6 +41,10 @@ public async Task RunAsync()
         // Example 3. Invoke the kernel with a prompt and allow the AI to automatically invoke functions
         OpenAIPromptExecutionSettings settings = new() { ToolCallBehavior = ToolCallBehavior.AutoInvokeKernelFunctions };
         WriteLine(await kernel.InvokePromptAsync("How many days until Christmas? Explain your thinking.", new(settings)));
+
+        // Example 4. Invoke the kernel with a prompt and allow the AI to automatically invoke functions that use enumerations
+        WriteLine(await kernel.InvokePromptAsync("Create a handy lime colored widget for me.", new(settings)));
+        WriteLine(await kernel.InvokePromptAsync("Create a beautiful scarlet colored widget for me.", new(settings)));
     }
 
     /// <summary>
@@ -51,6 +57,54 @@ public class TimeInformation
         public string GetCurrentUtcTime() => DateTime.UtcNow.ToString("R");
     }
 
+    /// <summary>
+    /// A plugin that returns the current time.
+    /// </summary>
+    public class WidgetFactory
+    {
+        [KernelFunction]
+        [Description("Creates a new widget of the specified type and color")]
+        public WidgetDetails CreateWidget([Description("The type of widget to be created")] WidgetType widgetType, [Description("The color of the widget to be created")] WidgetColor widgetColor)
+        {
+            return new()
+            {
+                SerialNumber = $"{widgetType}-{widgetColor}-{Guid.NewGuid()}",
+                Type = widgetType,
+                Color = widgetColor
+            };
+        }
+    }
+
+    [JsonConverter(typeof(JsonStringEnumConverter))]
+    public enum WidgetType
+    {
+        [Description("A widget that is useful.")]
+        Useful,
+
+        [Description("A widget that is decorative.")]
+        Decorative
+    }
+
+    [JsonConverter(typeof(JsonStringEnumConverter))]
+    public enum WidgetColor
+    {
+        [Description("Use when creating a red widget.")]
+        Red,
+
+        [Description("Use when creating a green widget.")]
+        Green,
+
+        [Description("Use when creating a blue widget.")]
+        Blue
+    }
+
+    public class WidgetDetails
+    {
+        public string SerialNumber { get; init; }
+        public WidgetType Type { get; init; }
+        public WidgetColor Color { get; init; }
+    }
+
     public Step2_Add_Plugins(ITestOutputHelper output) : base(output)
     {
     }