Fixed build errors and started an example project for development purposes and to be a starting-off point for newcomers to the slash command ecosystem,

Discord.Net.sln

@@ -42,6 +42,21 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Discord.Net.Examples", "src
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "idn", "samples\idn\idn.csproj", "{4A03840B-9EBE-47E3-89AB-E0914DF21AFB}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SlashCommandsExample", "SlashCommandsExample\SlashCommandsExample.csproj", "{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}"
+	ProjectSection(ProjectDependencies) = postProject
+		{6BDEEC08-417B-459F-9CA3-FF8BAB18CAC7} = {6BDEEC08-417B-459F-9CA3-FF8BAB18CAC7}
+		{9AFAB80E-D2D3-4EDB-B58C-BACA78D1EA30} = {9AFAB80E-D2D3-4EDB-B58C-BACA78D1EA30}
+		{BFC6DC28-0351-4573-926A-D4124244C04F} = {BFC6DC28-0351-4573-926A-D4124244C04F}
+		{E169E15A-E82C-45BF-8C24-C2CADB7093AA} = {E169E15A-E82C-45BF-8C24-C2CADB7093AA}
+		{47820065-3CFB-401C-ACEA-862BD564A404} = {47820065-3CFB-401C-ACEA-862BD564A404}
+		{DBF8B16E-5967-4480-8EDE-15D98A0DF0C4} = {DBF8B16E-5967-4480-8EDE-15D98A0DF0C4}
+		{FC67057C-E92F-4E1C-98BE-46F839C8AD71} = {FC67057C-E92F-4E1C-98BE-46F839C8AD71}
+		{91E9E7BD-75C9-4E98-84AA-2C271922E5C2} = {91E9E7BD-75C9-4E98-84AA-2C271922E5C2}
+		{688FD1D8-7F01-4539-B2E9-F473C5D699C7} = {688FD1D8-7F01-4539-B2E9-F473C5D699C7}
+		{078DD7E6-943D-4D09-AFC2-D2BA58B76C9C} = {078DD7E6-943D-4D09-AFC2-D2BA58B76C9C}
+		{BBA8E7FB-C834-40DC-822F-B112CB7F0140} = {BBA8E7FB-C834-40DC-822F-B112CB7F0140}
+	EndProjectSection
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -232,6 +247,18 @@ Global
 		{4A03840B-9EBE-47E3-89AB-E0914DF21AFB}.Release|x64.Build.0 = Release|Any CPU
 		{4A03840B-9EBE-47E3-89AB-E0914DF21AFB}.Release|x86.ActiveCfg = Release|Any CPU
 		{4A03840B-9EBE-47E3-89AB-E0914DF21AFB}.Release|x86.Build.0 = Release|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Debug|x64.Build.0 = Debug|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Debug|x86.ActiveCfg = Debug|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Debug|x86.Build.0 = Debug|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Release|Any CPU.Build.0 = Release|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Release|x64.ActiveCfg = Release|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Release|x64.Build.0 = Release|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Release|x86.ActiveCfg = Release|Any CPU
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27}.Release|x86.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -251,6 +278,7 @@ Global
 		{FC67057C-E92F-4E1C-98BE-46F839C8AD71} = {C7CF5621-7D36-433B-B337-5A2E3C101A71}
 		{47820065-3CFB-401C-ACEA-862BD564A404} = {BB59D5B5-E7B0-4BF4-8F82-D14431B2799B}
 		{4A03840B-9EBE-47E3-89AB-E0914DF21AFB} = {BB59D5B5-E7B0-4BF4-8F82-D14431B2799B}
+		{2CB2A016-CCEB-4A67-BC7B-098F114D7C27} = {BB59D5B5-E7B0-4BF4-8F82-D14431B2799B}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {D2404771-EEC8-45F2-9D71-F3373F6C1495}

SlashCommandsExample/Program.cs

@@ -0,0 +1,17 @@
+/*
+ * This project, is at this moment used for testing and debugging the new and experimental Slash Commands.
+ * After all testing has been done, and the project is ready to be integrated into the main Discord.Net ecosystem
+ * this project should be re-made into one that could be used as an example usage of the new Slash Command Service.
+ */
+using System;
+
+namespace SlashCommandsExample
+{
+	class Program
+	{
+		static void Main(string[] args)
+		{
+			Console.WriteLine("Hello World!");
+		}
+	}
+}

SlashCommandsExample/Properties/launchSettings.json

@@ -0,0 +1,7 @@
+{
+  "profiles": {
+    "SlashCommandsExample": {
+      "commandName": "Project"
+    }
+  }
+}

SlashCommandsExample/SlashCommandsExample.csproj

@@ -0,0 +1,8 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>netcoreapp3.1</TargetFramework>
+  </PropertyGroup>
+
+</Project>

src/Discord.Net.Rest/Entities/Interactions/RestApplicationCommand.cs

@@ -60,7 +60,7 @@ namespace Discord.Rest
             this.Description = model.Description;
 
             this.Options = model.Options.IsSpecified
-                ? model.Options.Value.Select(x => RestApplicationCommandOption.Create(x)).ToImmutableArray()
+                ? model.Options.Value.Select(x => RestApplicationCommandOption.Create(x)).ToImmutableArray().ToReadOnlyCollection()
                 : null;
         }
 

src/Discord.Net.Rest/Entities/Interactions/RestApplicationCommandOption.cs

@@ -60,11 +60,11 @@ namespace Discord.Rest
                 this.Required = model.Required.Value;
 
             this.Options = model.Options.IsSpecified
-                ? model.Options.Value.Select(x => Create(x)).ToImmutableArray()
+                ? model.Options.Value.Select(x => Create(x)).ToImmutableArray().ToReadOnlyCollection()
                 : null;
 
             this.Choices = model.Choices.IsSpecified
-                ? model.Choices.Value.Select(x => new RestApplicationCommandChoice(x)).ToImmutableArray()
+                ? model.Choices.Value.Select(x => new RestApplicationCommandChoice(x)).ToImmutableArray().ToReadOnlyCollection()
                 : null;
         }
 

src/Discord.Net.Rest/Extensions/EntityExtensions.cs

@@ -37,8 +37,8 @@ namespace Discord.Rest
         public static RoleTags ToEntity(this API.RoleTags model)
         {
             return new RoleTags(
-                model.BotId.IsSpecified ? model.BotId.Value : null,
-                model.IntegrationId.IsSpecified ? model.IntegrationId.Value : null,
+                model.BotId.IsSpecified ? model.BotId.Value : (ulong?)null,
+                model.IntegrationId.IsSpecified ? model.IntegrationId.Value : (ulong?)null,
                 model.IsPremiumSubscriber.IsSpecified ? true : false);
         }
         public static API.Embed ToModel(this Embed entity)

src/Discord.Net.WebSocket/Entities/Interaction/SocketApplicationCommandOption.cs

@@ -54,19 +54,19 @@ namespace Discord.WebSocket
 
             this.Default = model.Default.IsSpecified
                 ? model.Default.Value
-                : null;
+                : (bool?)null;
 
             this.Required = model.Required.IsSpecified
                 ? model.Required.Value
-                : null;
+                : (bool?)null;
 
             this.Choices = model.Choices.IsSpecified
-                ? model.Choices.Value.Select(x => SocketApplicationCommandChoice.Create(x)).ToImmutableArray()
-                : new ImmutableArray<SocketApplicationCommandChoice>();
+                ? model.Choices.Value.Select(x => SocketApplicationCommandChoice.Create(x)).ToImmutableArray().ToReadOnlyCollection()
+                : null;
 
             this.Options = model.Options.IsSpecified
-                ? model.Options.Value.Select(x => SocketApplicationCommandOption.Create(x)).ToImmutableArray()
-                : new ImmutableArray<SocketApplicationCommandOption>();
+                ? model.Options.Value.Select(x => SocketApplicationCommandOption.Create(x)).ToImmutableArray().ToReadOnlyCollection()
+                : null;
         }
 
         IReadOnlyCollection<IApplicationCommandOptionChoice> IApplicationCommandOption.Choices => Choices;

src/Discord.Net.WebSocket/Entities/Interaction/SocketInteractionData.cs

@@ -38,7 +38,7 @@ namespace Discord.WebSocket
             this.guildId = guildId;
 
             this.Options = model.Options.IsSpecified
-                ? model.Options.Value.Select(x => new SocketInteractionDataOption(x, this.Discord, guildId)).ToImmutableArray()
+                ? model.Options.Value.Select(x => new SocketInteractionDataOption(x, this.Discord, guildId)).ToImmutableArray().ToReadOnlyCollection()
                 : null;
         }
 

src/Discord.Net.WebSocket/Entities/Interaction/SocketInteractionDataOption.cs

@@ -36,7 +36,7 @@ namespace Discord.WebSocket
             this.guild = guild;
 
             this.Options = model.Options.IsSpecified
-                ? model.Options.Value.Select(x => new SocketInteractionDataOption(x, discord, guild)).ToImmutableArray()
+                ? model.Options.Value.Select(x => new SocketInteractionDataOption(x, discord, guild)).ToImmutableArray().ToReadOnlyCollection()
                 : null;
 
         }