Add new Bind overload

Author: HaoK

src/Microsoft.Extensions.Configuration.Binder/ConfigurationBinder.cs

@@ -56,6 +56,15 @@ public static object Get(this IConfiguration configuration, Type type)
             return BindInstance(type, instance: null, config: configuration);
         }
 
+        /// <summary>
+        /// Attempts to bind the given object instance to the configuration section specified by the key by matching property names against configuration keys recursively.
+        /// </summary>
+        /// <param name="configuration">The configuration instance to bind.</param>
+        /// <param name="sectionKey">The key of the configuration section to bind.</param>
+        /// <param name="instance">The object to bind.</param>
+        public static void Bind(this IConfiguration configuration, string sectionKey, object instance)
+            => configuration.GetSection(sectionKey).Bind(instance);
+
         /// <summary>
         /// Attempts to bind the given object instance to configuration values by matching property names against configuration keys recursively.
         /// </summary>
@@ -79,49 +88,49 @@ public static void Bind(this IConfiguration configuration, object instance)
         /// </summary>
         /// <typeparam name="T">The type to convert the value to.</typeparam>
         /// <param name="configuration">The configuration.</param>
-        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <param name="sectionKey">The key of the configuration section's value to convert.</param>
         /// <returns>The converted value.</returns>
-        public static T GetValue<T>(this IConfiguration configuration, string key)
+        public static T GetValue<T>(this IConfiguration configuration, string sectionKey)
         {
-            return GetValue(configuration, key, default(T));
+            return GetValue(configuration, sectionKey, default(T));
         }
 
         /// <summary>
         /// Extracts the value with the specified key and converts it to type T.
         /// </summary>
         /// <typeparam name="T">The type to convert the value to.</typeparam>
         /// <param name="configuration">The configuration.</param>
-        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <param name="sectionKey">The key of the configuration section's value to convert.</param>
         /// <param name="defaultValue">The default value to use if no value is found.</param>
         /// <returns>The converted value.</returns>
-        public static T GetValue<T>(this IConfiguration configuration, string key, T defaultValue)
+        public static T GetValue<T>(this IConfiguration configuration, string sectionKey, T defaultValue)
         {
-            return (T)GetValue(configuration, typeof(T), key, defaultValue);
+            return (T)GetValue(configuration, typeof(T), sectionKey, defaultValue);
         }
 
         /// <summary>
         /// Extracts the value with the specified key and converts it to the specified type.
         /// </summary>
         /// <param name="configuration">The configuration.</param>
         /// <param name="type">The type to convert the value to.</param>
-        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <param name="sectionKey">The key of the configuration section's value to convert.</param>
         /// <returns>The converted value.</returns>
-        public static object GetValue(this IConfiguration configuration, Type type, string key)
+        public static object GetValue(this IConfiguration configuration, Type type, string sectionKey)
         {
-            return GetValue(configuration, type, key, defaultValue: null);
+            return GetValue(configuration, type, sectionKey, defaultValue: null);
         }
 
         /// <summary>
         /// Extracts the value with the specified key and converts it to the specified type.
         /// </summary>
         /// <param name="configuration">The configuration.</param>
         /// <param name="type">The type to convert the value to.</param>
-        /// <param name="key">The configuration key for the value to convert.</param>
+        /// <param name="sectionKey">The key of the configuration section's value to convert.</param>
         /// <param name="defaultValue">The default value to use if no value is found.</param>
         /// <returns>The converted value.</returns>
-        public static object GetValue(this IConfiguration configuration, Type type, string key, object defaultValue)
+        public static object GetValue(this IConfiguration configuration, Type type, string sectionKey, object defaultValue)
         {
-            var value = configuration.GetSection(key).Value;
+            var value = configuration.GetSection(sectionKey).Value;
             if (value != null)
             {
                 return ConvertValue(type, value);

test/Microsoft.Extensions.Configuration.Binder.Test/ConfigurationBinderTests.cs

@@ -111,6 +111,29 @@ public void CanBindIConfigurationSection()
             Assert.Null(options.Section.Value);
         }
 
+        [Fact]
+        public void CanBindWithKeyOverload()
+        {
+            var dic = new Dictionary<string, string>
+            {
+                {"Section:Integer", "-2"},
+                {"Section:Boolean", "TRUe"},
+                {"Section:Nested:Integer", "11"},
+                {"Section:Virtual", "Sup"}
+            };
+            var configurationBuilder = new ConfigurationBuilder();
+            configurationBuilder.AddInMemoryCollection(dic);
+            var config = configurationBuilder.Build();
+
+            var options = new DerivedOptions();
+            config.Bind("Section", options);
+
+            Assert.True(options.Boolean);
+            Assert.Equal(-2, options.Integer);
+            Assert.Equal(11, options.Nested.Integer);
+            Assert.Equal("Derived:Sup", options.Virtual);
+        }
+
         [Fact]
         public void CanBindIConfigurationSectionWithDerivedOptionsSection()
         {