public interface ITestServices
    {
        int return123();
    }

 public class TestServices : ITestServices
    {
        public int return123()
        {
            return 123;
        }
    }

var builder = WebApplication.CreateBuilder(args);
// Add services to the container.
builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();
builder.Services.AddTransient<ITestServices, TestServices>();
var app = builder.Build();
// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}
app.UseHttpsRedirection();
app.UseAuthorization();
app.MapControllers();
app.Run();

[Route("[controller]/[action]")]
    [ApiController]
    public class TestController : ControllerBase
    {
        private readonly ITestServices _testServices;
        public TestController(ITestServices testServices)
        {
            _testServices= testServices;
        }
        [HttpGet]
        public int Get123() => _testServices.return123();
    }

 //瞬時注入服務(wù)接口
    public interface ITransient
    { }
    //作用域注入服務(wù)接口
    public interface IScoped
    { }
    //單例注入服務(wù)接口
    public interface ISingleton
    { }

 public static IServiceCollection RegisterAllServices(this IServiceCollection services)
        {
            //獲取當(dāng)前程序集
            var entryAssembly = Assembly.GetEntryAssembly();
            //獲取所有類型
            //!. null包容運(yùn)算符，當(dāng)你明確知道表達(dá)式的值不為null 使用!.（即null包容運(yùn)算符）可以告知編譯器這是預(yù)期行為，不應(yīng)發(fā)出警告
            //例: entryAssembly!.GetReferencedAssemblies() 正常
            //entryAssembly.GetReferencedAssemblies() 編譯器判斷entryAssembly有可能為null，變量下方出現(xiàn)綠色波浪線警告
            var types = entryAssembly!.GetReferencedAssemblies()//獲取當(dāng)前程序集所引用的外部程序集
                .Select(Assembly.Load)//裝載
                .Concat(new List<Assembly>() { entryAssembly })//與本程序集合并
                .SelectMany(x => x.GetTypes())//獲取所有類
                .Distinct();//排重
            //三種生命周期分別注冊
            Register<ITransient>(types, services.AddTransient, services.AddTransient);
            Register<IScoped>(types, services.AddScoped, services.AddScoped);
            Register<ISingleton>(types, services.AddSingleton, services.AddSingleton);
            return services;
        }
        /// <summary>
        /// 根據(jù)服務(wù)標(biāo)記的生命周期interface，不同生命周期注冊到容器里面
        /// </summary>
        /// <typeparam name="TLifetime">注冊的生命周期</typeparam>
        /// <param name="types">集合類型</param>
        /// <param name="register">委托：成對注冊</param>
        /// <param name="registerDirectly">委托：直接注冊服務(wù)實現(xiàn)</param>
        private static void Register<TLifetime>(IEnumerable<Type> types, Func<Type, Type, IServiceCollection> register, Func<Type, IServiceCollection> registerDirectly)
        {
            //找到所有標(biāo)記了Tlifetime生命周期接口的實現(xiàn)類
            var tImplements = types.Where(x => x.IsClass && !x.IsAbstract && x.GetInterfaces().Any(tinterface => tinterface == typeof(TLifetime)));
            //遍歷，挨個以其他所有接口為key，當(dāng)前實現(xiàn)為value注冊到容器中
            foreach (var t in tImplements)
            {
                //獲取除生命周期接口外的所有其他接口
                var interfaces = t.GetInterfaces().Where(x => x != typeof(TLifetime));
                if (interfaces.Any())
                {
                    foreach (var i in interfaces)
                    {
                        register(i, t);
                    }
                }
                //有時需要直接注入實現(xiàn)類本身
                registerDirectly(t);
            }
        }

builder.Services.RegisterAllServices();

 public interface ITestServices
    {
        int return123();
    }

 public class TestServices : ITestServices, ITransient
    {
        public int return123()
        {
            return 123;
        }
    }