下面的方法是检查给定类型是否继承或实现另一类型的通用方法:
Function InheritsOrImplements(child As Type, parent As Type) As Boolean
If child Is Nothing OrElse parent Is Nothing Then
Return False
End If
parent = resolveGenericTypeDefinition(parent)
If parent.IsAssignableFrom(child) Then
Return True
End If
Dim currentChild = If(child.IsGenericType, child.GetGenericTypeDefinition(), child)
While currentChild <> GetType(Object)
If parent = currentChild OrElse hasAnyInterfaces(parent, currentChild) Then
Return True
End If
currentChild = If(currentChild.BaseType IsNot Nothing AndAlso currentChild.BaseType.IsGenericType, currentChild.BaseType.GetGenericTypeDefinition(), currentChild.BaseType)
If currentChild Is Nothing Then
Return False
End If
End While
Return False
End Function
Function hasAnyInterfaces(parent As Type, child As Type) As Boolean
Return child.GetInterfaces().Any(Function(childInterface)
Dim currentInterface = If(childInterface.IsGenericType, childInterface.GetGenericTypeDefinition(), childInterface)
Return currentInterface = parent
End Function)
End Function
Function resolveGenericTypeDefinition(type As Type) As Type
Dim shouldUseGenericType = Not (type.IsGenericType AndAlso type.GetGenericTypeDefinition() <> type)
If type.IsGenericType AndAlso shouldUseGenericType Then
type = type.GetGenericTypeDefinition()
End If
Return type
End Function
从https://github.com/shaynevanasperen/Quarks/blob/master/Quarks/TypeExtensions/InheritsOrImplements.cs
用法摘自:
InheritsOrImplements(retType, GetType(IEnumerable))