Moved code and fixed code smells.

Author: askpt

src/OpenFeature/Model/FlagMetadata.cs

@@ -33,25 +33,25 @@ public FlagMetadata() : this([])
         return this.GetValue<double>(key);
     }
 
-    private T? GetValue<T>(string key) where T : struct
+    public string? GetString(string key)
     {
         var hasValue = this._metadata.TryGetValue(key, out var value);
         if (!hasValue)
         {
             return null;
         }
 
-        return value is T tValue ? tValue : throw new InvalidCastException($"Cannot cast {value?.GetType().ToString() ?? "Nullable"} to {typeof(T)}");
+        return value as string ?? throw new InvalidCastException($"Cannot cast {value?.GetType().ToString() ?? "Nullable"} to {typeof(string)}");
     }
 
-    public string? GetString(string key)
+    private T? GetValue<T>(string key) where T : struct
     {
         var hasValue = this._metadata.TryGetValue(key, out var value);
         if (!hasValue)
         {
             return null;
         }
 
-        return value is string tValue ? tValue : throw new InvalidCastException($"Cannot cast {value?.GetType().ToString() ?? "Nullable"} to {typeof(string)}");
+        return value is T tValue ? tValue : throw new InvalidCastException($"Cannot cast {value?.GetType().ToString() ?? "Nullable"} to {typeof(T)}");
     }
 }

test/OpenFeature.Tests/FlagMetadataTest.cs

@@ -104,5 +104,39 @@ public void GetDouble_Should_Return_Value_If_Key_Found()
             Assert.NotNull(result);
             Assert.Equal(1.2, result);
         }
+
+        [Fact]
+        public void GetString_Should_Return_Null_If_Key_Not_Found()
+        {
+            // Arrange
+            var metadata = new Dictionary<string, object>();
+            var flagMetadata = new FlagMetadata(metadata);
+
+            // Act
+            var result = flagMetadata.GetString("nonexistentKey");
+
+            // Assert
+            Assert.Null(result);
+        }
+
+        [Fact]
+        public void GetString_Should_Return_Value_If_Key_Found()
+        {
+            // Arrange
+            var metadata = new Dictionary<string, object>
+            {
+                {
+                    "stringKey", "11"
+                }
+            };
+            var flagMetadata = new FlagMetadata(metadata);
+
+            // Act
+            var result = flagMetadata.GetString("stringKey");
+
+            // Assert
+            Assert.NotNull(result);
+            Assert.Equal("11", result);
+        }
     }
 }