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PropertyAttributes Enumeration

Defines the attributes that can be associated with a property. These attribute values are defined in corhdr.h.

This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.

Namespace:  System.Reflection
Assemblies:   System.Reflection.Primitives (in System.Reflection.Primitives.dll)
  mscorlib (in mscorlib.dll)

'Declaration
<FlagsAttribute> _
Public Enumeration PropertyAttributes

Member nameDescription
Supported by the XNA FrameworkSupported by Portable Class LibraryHasDefaultSpecifies that the property has a default value.
Supported by the XNA FrameworkSupported by Portable Class LibraryNoneSpecifies that no attributes are associated with a property.
Supported by the XNA FrameworkReserved2Reserved.
Supported by the XNA FrameworkReserved3Reserved.
Supported by the XNA FrameworkReserved4Reserved.
Supported by the XNA FrameworkReservedMaskSpecifies a flag reserved for runtime use only.
Supported by the XNA FrameworkSupported by Portable Class LibraryRTSpecialNameSpecifies that the metadata internal APIs check the name encoding.
Supported by the XNA FrameworkSupported by Portable Class LibrarySpecialNameSpecifies that the property is special, with the name describing how the property is special.

To get the PropertyAttributes, first get the class Type. From the Type, get the PropertyInfo. From the PropertyInfo, get the Attributes.

The enumerated value is a number representing the bitwise OR of the attributes implemented on the method.

The following example builds three properties and displays the PropertyAttributes enumerated value. Note that the read-only property has no setter and thus cannot be changed by.Caption = statement.

Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic

' Make three properties, one read-write, one default, 
' and one read-only.  
Public Class Aproperty
    ' Define a read-write property. 
    Private myCaption As String = "A Default caption" 

    Public Property Caption() As String 
        Get 
            Return myCaption
        End Get 
        Set(ByVal Value As String)
            If myCaption <> value Then
                myCaption = value
            End If 
        End Set 
    End Property 
End Class 

Public Class Bproperty
    ' Define a default property. 
    Private myCaption As String = "B Default caption" 

    Default Public ReadOnly Property Item(ByVal index As Integer) As String 
        Get 
            Return "1" 
        End Get 
    End Property 

    Public Property Caption() As String 

        Get 
            Return myCaption
        End Get 
        Set(ByVal Value As String)
            If myCaption <> value Then
                myCaption = value
            End If 
        End Set 
    End Property 
End Class 

Public Class Cproperty
    ' Define a read-only property. 
    Private myCaption As String = "C Default caption" 

    Public ReadOnly Property Caption() As String 
        Get 
            Return myCaption
        End Get 
        'No setting is allowed because this property is read-only. 
    End Property 
End Class 


Class propertyattributesenum

    Public Shared Function Main() As Integer
        Console.WriteLine(ControlChars.CrLf & "Reflection.PropertyAttributes")

        ' Determine whether a property exists, and change its value. 
        Dim Mypropertya As New Aproperty()
        Dim Mypropertyb As New Bproperty()
        Dim Mypropertyc As New Cproperty()

        Console.Write(ControlChars.CrLf & "1. Mypropertya.Caption = " & _
           Mypropertya.Caption)

        Console.Write(ControlChars.CrLf & "1. Mypropertyb.Caption = " & _
           Mypropertyb.Caption)

        Console.Write(ControlChars.CrLf & "1. Mypropertyc.Caption = " & _
           Mypropertyc.Caption)

        ' Only Mypropertya can be changed because Mypropertyb is read-only.
        Mypropertya.Caption = "A- This is changed."
        Mypropertyb.Caption = "B- This is changed." 
        ' Note that Mypropertyc is not changed, because it is read-only.
        Console.Write(ControlChars.CrLf & ControlChars.CrLf & _
           "2. Mypropertya.Caption = " & Mypropertya.Caption)

        Console.Write(ControlChars.CrLf & "2. Mypropertyb.Caption = " & _
           Mypropertyb.Caption)

        Console.Write(ControlChars.CrLf + "2. Mypropertyc.Caption = " & _
           Mypropertyc.Caption)

        ' Get the PropertyAttributes Enumeration of the property. 
        ' Get the type. 
        Dim MyTypea As Type = Type.GetType("Aproperty")
        Dim MyTypeb As Type = Type.GetType("Bproperty")
        Dim MyTypec As Type = Type.GetType("Cproperty")

        ' Get the property attributes. 
        Dim Mypropertyinfoa As PropertyInfo = MyTypea.GetProperty("Caption")
        Dim Myattributesa As PropertyAttributes = Mypropertyinfoa.Attributes
        Dim Mypropertyinfob As PropertyInfo = MyTypeb.GetProperty("Item")
        Dim Myattributesb As PropertyAttributes = Mypropertyinfob.Attributes
        Dim Mypropertyinfoc As PropertyInfo = MyTypec.GetProperty("Caption")
        Dim Myattributesc As PropertyAttributes = Mypropertyinfoc.Attributes

        ' Display the property attributes value.
        Console.Write(ControlChars.CrLf & ControlChars.CrLf & "a- " & _
           Myattributesa.ToString())

        Console.Write(ControlChars.CrLf & "b- " & Myattributesb.ToString())

        Console.Write(ControlChars.CrLf & "c- " & Myattributesc.ToString())
        Return 0
    End Function'    End Function 
End Class 

' This example displays the following output to the console 

' Reflection.PropertyAttributes 

' 1. Mypropertya.Caption = A Default caption 
' 1. Mypropertyb.Caption = B Default caption 
' 1. Mypropertyc.Caption = C Default caption 

' 2. Mypropertya.Caption = A- This is changed. 
' 2. Mypropertyb.Caption = B- This is changed. 
' 2. Mypropertyc.Caption = C Default caption 

' a- None 
' b- None 
' c- None

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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