c# - 通用类无法接受直接指向通用类型限制的对象

Question

我有一个用如下所示的继承链定义的 C# 数据类:

public abstract class EntityBaseCore
public abstract class EntityBase : EntityBaseCore
public partial class AdmSite : EntityBase

还有一个像这样定义的泛型类:

public abstract class ViewModelSecurityBase<T> : Screen, where T : EntityBaseCore
public abstract class EditorViewModelBase<T> : ViewModelSecurityBase<T> where T : EntityBaseCore

我的 View 模型类如下所示:

public class SiteViewModel : EditorViewModelBase<AdmSite>

这失败了

The type 'Yargo.DataModel.AdmSite' cannot be used as type parameter 'T' in the generic type or method 'Yargo.Common.ViewModel.EditorViewModelBase'. There is no implicit reference conversion from 'Yargo.DataModel.AdmSite' to 'Yargo.DataModel.EntityBaseCore'

AdmSite 和 EntityBaseCode 之间的继承链似乎是直接的。我不明白为什么会失败。

Answer 1

下面的代码似乎对我有用。

public class Screen { }
public abstract class EntityBaseCore
{    }

public abstract class EntityBase : EntityBaseCore
{    }
public partial class AdmSite : EntityBase
{    }

public abstract class ViewModelSecurityBase<T> : Screen where T : EntityBaseCore
{    }
public abstract class EditorViewModelBase<T> : ViewModelSecurityBase<T> where T : EntityBaseCore
{    }

public class SiteViewModel : EditorViewModelBase<AdmSite>
{    }