I have a similar question to this one except I need to loop all the sub objects and change the property to read-only
我有一个类似的问题,除了我需要循环所有子对象并将属性更改为只读
Please check my code below. This one loop only the main object. When I tried to loop its sub objects, I got an overflow.
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,我得到了溢出。
Thanks.
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
1 个解决方案
#1
1
If you have objects with circular references, you might be visiting properties more than once.
如果您有包含循环引用的对象,则可能会多次访问属性。
In cases like this, I always find ways to 'mark' which items I've visited before, an idea which is commonly used when traversing graphs.
在这样的情况下,我总是想方设法“标记”我之前访问过哪些项目,这是在遍历图表时常用的一个想法。
#1
1
If you have objects with circular references, you might be visiting properties more than once.
如果您有包含循环引用的对象,则可能会多次访问属性。
In cases like this, I always find ways to 'mark' which items I've visited before, an idea which is commonly used when traversing graphs.
在这样的情况下,我总是想方设法“标记”我之前访问过哪些项目,这是在遍历图表时常用的一个想法。