Initial work for AbstractUI options

OwlCore.Wpf/Extensions/ResourceDictionaryExtensions.cs

@@ -0,0 +1,36 @@
+using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
+using System.Windows;
+
+namespace OwlCore.Wpf.Extensions
+{
+    public static class ResourceDictionaryExtensions
+    {
+        /// <summary>
+        /// Gets the value associated with the specified key.
+        /// </summary>
+        /// <param name="key">
+        /// The key of the value to get.
+        /// </param>
+        /// <param name="value">
+        /// When this method returns, contains the value associated with the specified key,
+        /// if the key is found; otherwise, <c>null</c>. This parameter is passed uninitialized.
+        /// </param>
+        /// <returns>
+        /// <c>true</c> if the <see cref="ResourceDictionary"/> contains an element with the specified key; otherwise, <c>false</c>.
+        /// </returns>
+        public static bool TryGetValue(this ResourceDictionary dict, object key, [MaybeNullWhen(false)] out object value)
+        {
+            try
+            {
+                value = dict[key];
+                return true;
+            }
+            catch (KeyNotFoundException)
+            {
+                value = null;
+                return false;
+            }
+        }
+    }
+}