給微軟的依賴注入框架寫一些擴展方法

時間 2020-02-26

標籤微軟依賴注入框架一些擴展方法欄目 Microsoft 简体版

原文原文鏈接

給微軟的依賴注入框架寫一些擴展方法

Intro

如今在項目裏大多都是直接使用微軟的依賴注入框架，而微軟的注入方式比較簡單，不如 AutoFac 使用起來靈活，因而想給微軟的依賴注入增長一些擴展，使得能夠像AutoFac 同樣比較靈活的註冊服務html

Extensions

RegisterTypeAsImplementedInterface

將類型註冊爲其實現的接口，好比 pubic class UserService:IUserService,IUserRepository{}，git

註冊 UserService 爲 IUserService 和 IUserRepositorygithub

等效於：框架

services.AddSingleton<IUserService, UserService>();
services.AddSingleton<IUserRepository, UserService>();

實現代碼：this

/// <summary>
/// RegisterTypeAsImplementedInterfaces
/// </summary>
/// <param name="services">services</param>
/// <param name="type">type</param>
/// <param name="serviceLifetime">service lifetime</param>
/// <returns>services</returns>
public static IServiceCollection RegisterTypeAsImplementedInterfaces(this IServiceCollection services, Type type, ServiceLifetime serviceLifetime = ServiceLifetime.Singleton)
{
    if (type != null)
    {
        foreach (var interfaceType in type.GetImplementedInterfaces())
        {
            services.Add(new ServiceDescriptor(interfaceType, type, serviceLifetime));
        }
    }
    return services;
}

RegisterAssemblyTypesAsImplementedInterface

在上面的基礎上，加載指定程序集中的類型（不指定程序集則使用當前應用程序域中全部程序集），能夠經過 typesFilter 來過濾要註冊的類型插件

使用示例：3d

services.RegisterAssemblyTypesAsImplementedInterface(t => !t.IsAbstract && t.IsClass && t.IsAssignableTo<IEventHandler>(), typeof(NoticeViewEventHandler).Assembly);

實現源碼：code

/// <summary>
/// RegisterTypeAsImplementedInterfaces
/// </summary>
/// <param name="services">services</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services,
    params Assembly[] assemblies)
    => RegisterAssemblyTypesAsImplementedInterfaces(services, typesFilter: null, ServiceLifetime.Singleton, assemblies);

/// <summary>
/// RegisterTypeAsImplementedInterfaces
/// </summary>
/// <param name="services">services</param>
/// <param name="serviceLifetime">service lifetime</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services,
    ServiceLifetime serviceLifetime, params Assembly[] assemblies)
    => RegisterAssemblyTypesAsImplementedInterfaces(services, typesFilter: null, serviceLifetime, assemblies);

/// <summary>
/// RegisterTypeAsImplementedInterfaces, singleton by default
/// </summary>
/// <param name="services">services</param>
/// <param name="typesFilter">filter types to register</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services, Func<Type, bool> typesFilter, params Assembly[] assemblies)
    => RegisterAssemblyTypesAsImplementedInterfaces(services, typesFilter: typesFilter, ServiceLifetime.Singleton, assemblies);

/// <summary>
/// RegisterTypeAsImplementedInterfaces
/// </summary>
/// <param name="services">services</param>
/// <param name="typesFilter">filter types to register</param>
/// <param name="serviceLifetime">service lifetime</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypesAsImplementedInterfaces(this IServiceCollection services, Func<Type, bool> typesFilter, ServiceLifetime serviceLifetime, params Assembly[] assemblies)
{
    if (assemblies == null || assemblies.Length == 0)
    {
        assemblies = ReflectHelper.GetAssemblies();
    }

    var types = assemblies
        .Select(assembly => assembly.GetExportedTypes())
        .SelectMany(t => t);
    if (typesFilter != null)
    {
        types = types.Where(typesFilter);
    }

    foreach (var type in types)
    {
        foreach (var implementedInterface in type.GetImplementedInterfaces())
        {
            services.Add(new ServiceDescriptor(implementedInterface, type, serviceLifetime));
        }
    }

    return services;
}

RegisterAssemblyTypes

註冊類型，這至關於 AutoFac 中 RegisterAssemblyTypes().AsSelf()htm

services.RegisterAssemblyTypes(t => !t.IsAbstract && t.IsClass && t.IsAssignableTo<IEventHandler>(), typeof(NoticeViewEventHandler).Assembly);

實現源碼：接口

/// <summary>
/// RegisterAssemblyTypes
/// </summary>
/// <param name="services">services</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services, params Assembly[] assemblies)
    => RegisterAssemblyTypes(services, null, ServiceLifetime.Singleton, assemblies);

/// <summary>
/// RegisterAssemblyTypes
/// </summary>
/// <param name="services">services</param>
/// <param name="serviceLifetime">service lifetime</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services,
    ServiceLifetime serviceLifetime, params Assembly[] assemblies)
    => RegisterAssemblyTypes(services, null, serviceLifetime, assemblies);

/// <summary>
/// RegisterAssemblyTypes
/// </summary>
/// <param name="services">services</param>
/// <param name="typesFilter">filter types to register</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services,
    Func<Type, bool> typesFilter, params Assembly[] assemblies)
    => RegisterAssemblyTypes(services, typesFilter, ServiceLifetime.Singleton, assemblies);

/// <summary>
/// RegisterAssemblyTypes
/// </summary>
/// <param name="services">services</param>
/// <param name="typesFilter">filter types to register</param>
/// <param name="serviceLifetime">service lifetime</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyTypes(this IServiceCollection services, Func<Type, bool> typesFilter, ServiceLifetime serviceLifetime, params Assembly[] assemblies)
{
    if (assemblies == null || assemblies.Length == 0)
    {
        assemblies = ReflectHelper.GetAssemblies();
    }

    var types = assemblies
        .Select(assembly => assembly.GetExportedTypes())
        .SelectMany(t => t);
    if (typesFilter != null)
    {
        types = types.Where(typesFilter);
    }

    foreach (var type in types)
    {
        services.Add(new ServiceDescriptor(type, type, serviceLifetime));
    }

    return services;
}

ServiceModule

在 AutoFac 中有一個 Module 的概念能夠讓咱們更方便的註冊，通常能夠在一個 Module 裏註冊須要服務註冊的服務，這樣註冊的好處在於容易作插件化，新的插件須要註冊什麼樣的服務，外界並不知道，若是用 Module 的註冊方式，我只須要調用插件中的 Module 就能夠註冊所須要的服務了

IServiceModule

相似於 AutoFac 中的 Module，咱們也能夠定義一個 IServiceModule，定義一個 ConfigueServices(IServiceCollection services) 的方法用來註冊服務

public interface IServiceModule
{
    void ConfigureServices(IServiceCollection services);
}

ServiceModule Demo

public class BusinessServiceModule : IServiceModule
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddEFRepository();
        services.AddBLL();
        services.TryAddScoped<ReservationHelper>();
        services.TryAddSingleton<CaptchaVerifyHelper>();
        services.TryAddSingleton<OperLogHelper>();
    }
}

RegisterAssemblyModules

上面咱們定義了一個 Module，下面來定義一個擴展方法來註冊 module 中的服務信息

使用示例：

// load service modules
services.RegisterAssemblyModules(pluginAssemblies);

實現源碼：

/// <summary>
/// RegisterAssemblyModules
/// </summary>
/// <param name="services">services</param>
/// <param name="assemblies">assemblies</param>
/// <returns>services</returns>
public static IServiceCollection RegisterAssemblyModules(
    [NotNull] this IServiceCollection services, params Assembly[] assemblies)
{
    if (assemblies == null || assemblies.Length == 0)
    {
        assemblies = ReflectHelper.GetAssemblies();
    }
    foreach (var type in assemblies.SelectMany(ass => ass.GetTypes())
        .Where(t => t.IsClass && !t.IsAbstract && typeof(IServiceModule).IsAssignableFrom(t))
    )
    {
        try
        {
            if (Activator.CreateInstance(type) is IServiceModule module)
            {
                module.ConfigureServices(services);
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e);
        }
    }

    return services;
}