“ ServiceCollection”不包含“ AddSingleton”的定义 [英] 'ServiceCollection' does not contain a definition for 'AddSingleton'

问题描述

我一直在通过程序类将依赖项注册到我的IOC容器中，但是它很混乱。我决定写一个DI提供程序，在其中提供并注册依赖项。

I've been registering my dependencies to my IOC container via the program class, but it got messy. I decided to write a DI provider which provided and registered dependencies inside of it.

在我开始用代码解释之前，这是VS给的完整编译错误。

Before I begin explaining with code, here is the full compilation error VS gives.

'ServiceCollection'不包含'AddSingleton'的定义
无法解析符号'AddSingleton'

'ServiceCollection' does not contain a definition for 'AddSingleton' Cannot resolve symbol 'AddSingleton'

我试图变得尽可能干净，在 DependencyProvider

I tried to be as clean as possible, inherting ServiceCollection class inside DependencyProvider

public class DependencyProvider : ServiceCollection, IDependencyProvider
{
    public DependencyProvider() : base()
    {
        Register();
    }

    public void Register()
    {
        base.AddSingleton<IContext, Context>(); // this line errors
        new ServiceCollection().AddSingleton<IContext, Context>(); // this line works
    }
}

这里是IDependencyProvider接口

Here is the IDependencyProvider interface

public interface IDependencyProvider : IServiceCollection
{
    void Register();
}

我可以不这样做，还是我做错了什么？我真的希望它是可行的，因为该解决方案似乎超级干净，目的是创建一个新的ServiceCollection实例并为其使用字段。

Can I not do this, or am I just doing something wrong? I really hope its possible, as the solution seems super clean, apose to creating a new instance of ServiceCollection and using the field for it.

只是为了澄清错误，我无法访问 ServiceCollection 上的任何基本方法，像这样

Just to clarify the error, I can't access any of the base methods on ServiceCollection, like so

base.AddSingleton<IContext, Context>();

但是当创建新的实例内联时，此行有效

But this line works, when making a new instance inline

new ServiceCollection().AddSingleton<IContext, Context>();

推荐答案

基础关键字不能解析扩展方法。您想做的是：

The base keyword does not resolve extension methods. What you want to do is:

this.AddSingleton<IContext, Context>();

这篇关于“ ServiceCollection”不包含“ AddSingleton”的定义的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！