#20: add method to check if type is installed

LightweightIocContainer/Interfaces/IIocContainer.cs

@@ -57,5 +57,12 @@ namespace LightweightIocContainer.Interfaces
         /// </summary>
         /// <typeparam name="T">The <see cref="Type"/> to clear the multiton instances</typeparam>
         void ClearMultitonInstances<T>();
+
+        /// <summary>
+        /// Is the given <see cref="Type"/> registered with this <see cref="IIocContainer"/>
+        /// </summary>
+        /// <typeparam name="T">The given <see cref="Type"/></typeparam>
+        /// <returns>True if the given <see cref="Type"/> is registered with this <see cref="IIocContainer"/>, false if not</returns>
+        bool IsTypeRegistered<T>();
     }
 }

LightweightIocContainer/IocContainer.cs

@@ -284,6 +284,13 @@ namespace LightweightIocContainer
             _multitons.Remove(multitonInstance);
         }
 
+        /// <summary>
+        /// Is the given <see cref="Type"/> registered with this <see cref="IocContainer"/>
+        /// </summary>
+        /// <typeparam name="T">The given <see cref="Type"/></typeparam>
+        /// <returns>True if the given <see cref="Type"/> is registered with this <see cref="IocContainer"/>, false if not</returns>
+        public bool IsTypeRegistered<T>() => _registrations.Any(registration => registration.InterfaceType == typeof(T));
+
         /// <summary>
         /// The <see cref="IDisposable.Dispose"/> method
         /// </summary>

LightweightIocContainer/LightweightIocContainer.xml

@@ -254,6 +254,13 @@
             </summary>
             <typeparam name="T">The <see cref="T:System.Type"/> to clear the multiton instances</typeparam>
         </member>
+        <member name="M:LightweightIocContainer.Interfaces.IIocContainer.IsTypeRegistered``1">
+            <summary>
+            Is the given <see cref="T:System.Type"/> registered with this <see cref="T:LightweightIocContainer.Interfaces.IIocContainer"/>
+            </summary>
+            <typeparam name="T">The given <see cref="T:System.Type"/></typeparam>
+            <returns>True if the given <see cref="T:System.Type"/> is registered with this <see cref="T:LightweightIocContainer.Interfaces.IIocContainer"/>, false if not</returns>
+        </member>
         <member name="T:LightweightIocContainer.Interfaces.Installers.IAssemblyInstaller">
             <summary>
             An <see cref="T:LightweightIocContainer.Interfaces.Installers.IIocInstaller"/> that installs all <see cref="T:LightweightIocContainer.Interfaces.Installers.IIocInstaller"/>s for its given <see cref="T:System.Reflection.Assembly"/>
@@ -437,6 +444,13 @@
             </summary>
             <typeparam name="T">The <see cref="T:System.Type"/> to clear the multiton instances</typeparam>
         </member>
+        <member name="M:LightweightIocContainer.IocContainer.IsTypeRegistered``1">
+            <summary>
+            Is the given <see cref="T:System.Type"/> registered with this <see cref="T:LightweightIocContainer.IocContainer"/>
+            </summary>
+            <typeparam name="T">The given <see cref="T:System.Type"/></typeparam>
+            <returns>True if the given <see cref="T:System.Type"/> is registered with this <see cref="T:LightweightIocContainer.IocContainer"/>, false if not</returns>
+        </member>
         <member name="M:LightweightIocContainer.IocContainer.Dispose">
             <summary>
             The <see cref="M:System.IDisposable.Dispose"/> method

Test.LightweightIocContainer/IocContainerTest.cs

@@ -355,5 +355,14 @@ namespace Test.LightweightIocContainer
             Assert.AreNotSame(resolvedTest2, resolvedTest4);
             Assert.AreNotSame(resolvedTest3, resolvedTest5);
         }
+
+        [Test]
+        public void TestIsTypeRegistered()
+        {
+            Assert.False(_iocContainer.IsTypeRegistered<ITest>());
+
+            _iocContainer.Register(RegistrationFactory.Register<ITest, Test>());
+            Assert.True(_iocContainer.IsTypeRegistered<ITest>());
+        }
     }
 }