ASP.NET Core 中 AddMvc() 與 AddMvcCore() 的差別

ASP.NET Core 將過去 ASP.NET MVC 與 ASP.NET Web API 兩套 framework 整合在一起，對於開發人員是種福音：不用再想到底該引用哪個 NameSpace、不用再為該繼承哪個類別煩惱、不用再記兩種開發模式(到底該用 action filter 還是 MessageHandler)，不過實際上在 ASP.NET Core 中還是有 AddMvc() 與 AddMvcCore() 兩種服務註冊方式

其中差別剛看到時實在沒什麼想法，幸虧 ASP.NET Core 程式碼都是 open source，覺得有疑問馬上可以翻一下，今天就簡單紀錄一下自己看到的差異

基本環境說明

macOS Mojave 10.14.5
.NET Core SDK 2.2.107 (.NET Core Runtime 2.2.5)

AddMvcCore

完整程式碼請參考 AddMvcCore

程式碼節錄如下：

public static IMvcCoreBuilder AddMvcCore(this IServiceCollection services)
{
    if (services == null)
    {
        throw new ArgumentNullException(nameof(services));
    }
    var partManager = GetApplicationPartManager(services);
    services.TryAddSingleton(partManager);
    ConfigureDefaultFeatureProviders(partManager);
    ConfigureDefaultServices(services);
    AddMvcCoreServices(services);
    var builder = new MvcCoreBuilder(services, partManager);
    return builder;
}

AddMvc

完整程式碼請參考 AddMvc

程式碼節錄如下：

public static IMvcBuilder AddMvc(this IServiceCollection services)
{
    if (services == null)
    {
        throw new ArgumentNullException(nameof(services));
    }
    services.AddControllersWithViews();
    return services.AddRazorPages();
}
....

public static IMvcBuilder AddControllersWithViews(this IServiceCollection services)
{
    if (services == null)
    {
        throw new ArgumentNullException(nameof(services));
    }
    var builder = AddControllersWithViewsCore(services);
    return new MvcBuilder(builder.Services, builder.PartManager);
}

private static IMvcCoreBuilder AddControllersWithViewsCore(IServiceCollection services)
{
    var builder = AddControllersCore(services)
        .AddViews()
        .AddRazorViewEngine()
        .AddCacheTagHelper();
    AddTagHelpersFrameworkParts(builder.PartManager);
    return builder;
}
....

private static IMvcCoreBuilder AddControllersCore(IServiceCollection services)
{
    // This method excludes all of the view-related services by default.
    return services
        .AddMvcCore()
        .AddApiExplorer()
        .AddAuthorization()
        .AddCors()
        .AddDataAnnotations()
        .AddFormatterMappings();
}