Reintroduced GetTopic(), indexer as [Obsolete]

The `TopicCollection` and `ReadOnlyTopicCollection` were renamed to `KeyedTopicCollection` and `ReadOnlyKeyedTopicCollection`. In their place, a non-keyed version was introduced. Callers of these classes may still expected `GetTopic()` to be in place. We obviously can't mark `TopicCollection` and `ReadOnlyTopicCollection` as `[Obsolete]` since they've been reintroduced in a new capacity, but we can introduce these common members as `[Obsolete]` as a means of instructing callers how to migrate to the new classes.

Author: JeremyCaney

OnTopic/Collections/ReadOnlyTopicCollection.cs

@@ -3,6 +3,7 @@
 | Client        Ignia, LLC
 | Project       Topics Library
 \=============================================================================================================================*/
+using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 
@@ -26,5 +27,25 @@ public class ReadOnlyTopicCollection : ReadOnlyCollection<Topic> {
     public ReadOnlyTopicCollection(IList<Topic>? innerCollection = null) : base(innerCollection?? new List<Topic>()) {
     }
 
+    /*==========================================================================================================================
+    | METHOD: GET TOPIC
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <inheritdoc cref="ReadOnlyKeyedTopicCollection{T}.GetTopic(String)"/>
+    [Obsolete(
+      "The GetTopic() method is not implemented on ReadOnlyTopicCollection. Use ReadOnlyKeyedTopicCollection instead.",
+      true
+    )]
+    public Topic? GetValue(string key) => throw new NotImplementedException();
+
+    /*==========================================================================================================================
+    | INDEXER
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <inheritdoc cref="ReadOnlyKeyedTopicCollection{T}"/>
+    [Obsolete(
+      "Indexing by key is not implemented on ReadOnlyTopicCollection. Use ReadOnlyKeyedTopicCollection instead.",
+      true
+    )]
+    public Topic this[string key] => throw new ArgumentOutOfRangeException(nameof(key));
+
   } //Class
 } //Namespace

OnTopic/Collections/TopicCollection.cs

@@ -3,6 +3,7 @@
 | Client        Ignia, LLC
 | Project       Topics Library
 \=============================================================================================================================*/
+using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Linq;
@@ -35,5 +36,19 @@ public class TopicCollection : Collection<Topic> {
     /// </summary>
     public ReadOnlyTopicCollection AsReadOnly() => new(this);
 
+    /*==========================================================================================================================
+    | METHOD: GET TOPIC
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <inheritdoc cref="KeyedTopicCollection{T}.GetTopic(String)"/>
+    [Obsolete("The GetTopic() method is not implemented on TopicCollection. Use KeyedTopicCollection instead.", true)]
+    public Topic? GetValue(string key) => throw new NotImplementedException();
+
+    /*==========================================================================================================================
+    | INDEXER
+    \-------------------------------------------------------------------------------------------------------------------------*/
+    /// <inheritdoc cref="KeyedTopicCollection{T}"/>
+    [Obsolete("Indexing by key is not implemented on the TopicCollection. Use the KeyedTopicCollection instead.",true)]
+    public Topic this[string key] => throw new ArgumentOutOfRangeException(nameof(key));
+
   } //Class
 } //Namespace