Question

有没有办法扩展现有的绑定语法（例如扩展方法），这将允许我们有这样的东西：

Bind<IRepository>().ToProvider<MyProvider<MyRepository>>().WhenCustom<SomeType>()

Answer 1

为IBindingWhenSyntax<T>编写扩展方法，并使用现有的When重载来实现您的逻辑：

class BindingWhenExtensions
{
   public IBindingInNamedWithOrOnSyntax<T> WhenCustom<T>(
       this IBindingWhenSyntax<T> syntax)
   { 
        return syntax.When(r => true); 
   }
}

Answer 2

重新构建问题（与评论一致）您想要创建一个类似于以下签名的扩展程序;

public static IBindingInNamedWithOrOnSyntax<T> WhenCustom<TParent>(
            this IBindingWhenSyntax<T> binding)

据我所知，我们无法像Ninject一样干净利落地扩展，因为正如你正确地提到T这里定义的on an interface是我们的扩展所不知道的。

所以我们的扩展签名必须是;

public static IBindingInNamedWithOrOnSyntax<T> WhenCustom<T>(
            this IBindingWhenSyntax<T> binding)

此时我认为能够成功传递TParent的唯一方法是删除泛型参数并将其作为标准类型参数传递（或传递多种类型）;

 public static IBindingInNamedWithOrOnSyntax<T> WhenCustom(
            this IBindingWhenSyntax<T> binding, params Type[] parents)

这仍然与Ninjects自己的绑定语法方法一致;

/// <summary>
/// Indicates that the binding should be used only for injections on the specified types.
/// Types that derive from one of the specified types are considered as valid targets.
/// Should match at lease one of the targets.
/// </summary>
/// <param name="parents">The types to match.</param>
/// <returns>The fluent syntax.</returns>
IBindingInNamedWithOrOnSyntax<T> WhenInjectedInto(params Type[] parents);

令人遗憾的是，我们没有“纯粹”泛型的延伸。

如何扩展Ninject绑定语法

2 个答案: