.Net Core依赖注入原理简单实现

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var app = new MyApplication();   app.Services.AddTransient<ITestServices, TestServices>();   app.Services.AddTransient<ITestServices2, TestServices2>();   var a = app.Services.GetService<ITestServices>();   var b = app.Services.GetService<ITestServices2>();   Console.WriteLine(a.GetData());   Console.WriteLine(b.GetData()); public class MyApplication {     public Dictionary<Type, Type> Services { get; set; } = new Dictionary<Type, Type>(); }   public static class MyApplicationExtensions {     public static Dictionary<Type, Type> AddTransient<IServices, Impliment>(this Dictionary<Type, Type> services) where IServices : class     where Impliment : class, IServices     {         services.Add(typeof(IServices), typeof(Impliment));         return services;     }     public static object GetService(this Dictionary<Type, Type> services, Type tServices)     {         var tImplement = services.ContainsKey(tServices) ? services[tServices] : null;           object? value = null;           if (tImplement != null)         {             var ctor = tImplement.GetConstructors().OrderByDescending(x => x.GetParameters().Count()).FirstOrDefault();               var ctorParams = ctor.GetParameters();               var ParamsList = new List<object>();               //循环加递归依次拿到对应构造参数               foreach (var ctorParam in ctorParams)             {                 ParamsList.Add(services.GetService(ctorParam.ParameterType));             }               value = ctor.Invoke(ParamsList.ToArray());         }           return value;     }       public static IServices GetService<IServices>(this Dictionary<Type, Type> services)     {         return (IServices)services.GetService(typeof(IServices));     } }