moved SmallInjector to new Project.

2019-07-20 22:58:53 +02:00
parent e4ce2a472a
commit 8954cd82fc
9 changed files with 84 additions and 50 deletions
--- a/SmallInjector/Container.cs
+++ b/SmallInjector/Container.cs
@@ -0,0 +1,58 @@
+using System;
+using System.Collections.Generic;
+
+namespace SmallInjector
+{
+    /// <summary>
+    /// A small dependency injector to demonstrate the pattern.
+    /// </summary>
+    public class Container : IContainer
+    {
+        private readonly Dictionary<Type, RegisteredType> _container = new Dictionary<Type, RegisteredType>();
+
+        /// <inheritdoc/>
+        public void RegisterType<TService, TInterface>(bool isSingleton, TService instance = default) where TService : TInterface
+        {
+            _container.Add(typeof(TInterface), new RegisteredType(typeof(TService), isSingleton, null));
+        }
+
+        /// <inheritdoc/>
+        public void RegisterType<TService>(bool isSingleton, TService instance = default) => RegisterType<TService, TService>(isSingleton, instance);
+
+        /// <inheritdoc/>
+        public TService Resolve<TService>() => (TService)Resolve(typeof(TService));
+
+        /// <inheritdoc/>
+        public object Resolve(Type serviceInterface)
+        {
+            if (!_container.TryGetValue(serviceInterface, out var registeredType))
+                throw new Exception("Can't resolve dependency " + serviceInterface);
+
+            if (registeredType.IsSingleton && registeredType.Instance != null)
+                return registeredType.Instance;
+            var constructor = registeredType.ServiceType.GetConstructors()[0];
+            var parameters = constructor.GetParameters();
+            var constructorParameters = new object[parameters.Length];
+            for (var i = 0; i < parameters.Length; i++)
+            {
+                constructorParameters[i] = Resolve(parameters[i].ParameterType);
+            }
+            var instance = constructor.Invoke(constructorParameters);
+            return registeredType.IsSingleton ? (registeredType.Instance = instance) : instance;
+        }
+
+        private class RegisteredType
+        {
+            public RegisteredType(Type serviceType, bool isSingleton, object instance)
+            {
+                ServiceType = serviceType;
+                IsSingleton = isSingleton;
+                Instance = instance;
+            }
+
+            public readonly bool IsSingleton;
+            public readonly Type ServiceType;
+            public object Instance { get; set; }
+        }
+    }
+}