Question

我有一个与this one类似的问题，除了我需要循环所有子对象并将属性更改为只读

请检查下面的代码。这一循环只是主要对象。当我试图循环其子对象时，我遇到了溢出。

感谢。



Public Class ReadOnlyTypeDescriptor 
    Inherits CustomTypeDescriptor 
    Private mComponent As Object 

    Public Sub New(ByVal component As Object) 
        MyBase.New(TypeDescriptor.GetProvider(component).GetTypeDescriptor(component)) 
        mComponent = component 
    End Sub 

    Public Overloads Overrides Function GetProperties(ByVal attributes As Attribute()) As PropertyDescriptorCollection 
        Dim inPdc As PropertyDescriptorCollection = MyBase.GetProperties(attributes) 

        Dim pdcs As PropertyDescriptor() = New PropertyDescriptor(inPdc.Count - 1) {} 
        For i As Integer = 0 To pdcs.Length - 1 
            If inPdc(i).IsReadOnly Then 
                pdcs(i) = inPdc(i) 
            Else 
                pdcs(i) = New ReadOnlyPropertyDescriptor(inPdc(i)) 
            End If 
        Next 

        Return New PropertyDescriptorCollection(pdcs, True) 
    End Function 

    Public Overloads Overrides Function GetProperties() As PropertyDescriptorCollection 
        Return GetProperties(Nothing) 
    End Function 

    Private Class ReadOnlyPropertyDescriptor 
        Inherits PropertyDescriptor 
        Private mParent As PropertyDescriptor 

        Public Sub New(ByVal parent As PropertyDescriptor) 
            MyBase.New(parent, New Attribute() {ReadOnlyAttribute.Yes}) 
            mParent = parent 
        End Sub 

        Public Overloads Overrides Function CanResetValue(ByVal component As Object) As Boolean 
            Return False 
            ' Read Only 
        End Function 

        Public Overloads Overrides ReadOnly Property ComponentType() As Type 
            Get 
                Return mParent.ComponentType 
            End Get 
        End Property 

        Public Overloads Overrides Function GetValue(ByVal component As Object) As Object 
            Return mParent.GetValue(component) 
        End Function 

        Public Overloads Overrides ReadOnly Property IsReadOnly() As Boolean 
            Get 
                Return True 
            End Get 
        End Property 

        Public Overloads Overrides ReadOnly Property PropertyType() As Type 
            Get 
                Return mParent.PropertyType 
            End Get 
        End Property 

        Public Overloads Overrides Sub ResetValue(ByVal component As Object) 
            ' Read Only 
        End Sub 

        Public Overloads Overrides Sub SetValue(ByVal component As Object, ByVal value As Object) 
            ' Read Only 
        End Sub 

        Public Overloads Overrides Function ShouldSerializeValue(ByVal component As Object) As Boolean 
            Return mParent.ShouldSerializeValue(component) 
        End Function 
    End Class 
End Class

Answer 1

如果您有包含循环引用的对象，则可能会多次访问属性。

在这种情况下，我总能找到方法来“标记”我以前访问过哪些项目，这是在遍历图表时常用的一种想法。

如何获取对象及其子对象的所有属性

1 个答案: