Type.Attributes Property
Microsoft Silverlight will reach end of support after October 2021. Learn more.
Gets the attributes associated with the Type.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public ReadOnly Property Attributes As TypeAttributes
public TypeAttributes Attributes { get; }
Property Value
Type: System.Reflection.TypeAttributes
A TypeAttributes object representing the attribute set of the Type, unless the Type represents a generic type parameter, in which case the value is unspecified.
Remarks
If the current Type represents a constructed generic type, this property returns the attributes of the generic type definition. For example, the attributes returned for MyGenericClass<int> (MyGenericClass(Of Integer) in Visual Basic) are the attributes of MyGenericClass<T> (MyGenericClass(Of T) in Visual Basic).
If the current Type represents a generic type parameter — that is, if the IsGenericParameter property returns true — the TypeAttributes value returned by this property is unspecified.
Examples
The following example shows the use of the Type.Attributes property. The fact that there is a member in each of several groupings that has the value zero means that you must use masks before testing for those members.
For most purposes, properties like IsClass, IsAutoLayout, and IsSpecialName are easier to use than type attributes.
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To run this example, see Building Examples That Use a Demo Method and a TextBlock Control. |
Imports System.Reflection
Friend Structure S
Public X As Integer
End Structure
Public MustInherit Class Example
Protected NotInheritable Class NestedClass
End Class
Public Interface INested
End Interface
Private Shared outputBlock As System.Windows.Controls.TextBlock
Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
Example.outputBlock = outputBlock
DisplayAttributes(GetType(Example))
DisplayAttributes(GetType(NestedClass))
DisplayAttributes(GetType(INested))
DisplayAttributes(GetType(S))
End Sub
Private Shared Sub DisplayAttributes(ByVal t As Type)
outputBlock.Text &= "Attributes for type " & t.Name & ":" & vbLf
Dim attr As TypeAttributes = t.Attributes
' To test for visibility attributes, you must use the visibility
' mask.
Dim visibility As TypeAttributes = attr And TypeAttributes.VisibilityMask
Select Case visibility
Case TypeAttributes.NotPublic:
outputBlock.Text &= " ...is not Public" & vbLf
Case TypeAttributes.Public:
outputBlock.Text &= " ...is Public" & vbLf
Case TypeAttributes.NestedPublic:
outputBlock.Text &= " ...is nested and Public" & vbLf
Case TypeAttributes.NestedPrivate:
outputBlock.Text &= " ...is nested and Private" & vbLf
Case TypeAttributes.NestedFamANDAssem:
outputBlock.Text &= " ...is nested, and inheritable only within the assembly" & _
vbLf & " (cannot be declared in Visual Basic)" & vbLf
Case TypeAttributes.NestedAssembly:
outputBlock.Text &= " ...is nested and Friend" & vbLf
Case TypeAttributes.NestedFamily:
outputBlock.Text &= " ...is nested and Protected" & vbLf
Case TypeAttributes.NestedFamORAssem:
outputBlock.Text &= " ...is nested and Protected Friend" & vbLf
End Select
Dim layout As TypeAttributes = attr And TypeAttributes.LayoutMask
Select Case layout
Case TypeAttributes.AutoLayout:
outputBlock.Text &= " ...is AutoLayout" & vbLf
Case TypeAttributes.SequentialLayout:
outputBlock.Text &= " ...is SequentialLayout" & vbLf
Case TypeAttributes.ExplicitLayout:
outputBlock.Text &= " ...is ExplicitLayout" & vbLf
End Select
Dim classSemantics As TypeAttributes = attr And TypeAttributes.ClassSemanticsMask
Select Case classSemantics
Case TypeAttributes.Class:
If t.IsValueType Then
outputBlock.Text &= " ...is a value type" & vbLf
Else
outputBlock.Text &= " ...is a class" & vbLf
End If
Case TypeAttributes.Interface:
outputBlock.Text &= " ...is an interface" & vbLf
End Select
If 0 <> (attr And TypeAttributes.Abstract) Then _
outputBlock.Text &= " ...is MustInherit" & vbLf
If 0 <> (attr And TypeAttributes.Sealed) Then _
outputBlock.Text &= " ...is NotInheritable" & vbLf
End Sub
End Class
' This example produces the following output:
'
'Attributes for type Example:
' ...is Public
' ...is AutoLayout
' ...is a class
' ...is MustInherit
'Attributes for type NestedClass:
' ...is nested and Protected
' ...is AutoLayout
' ...is a class
' ...is NotInheritable
'Attributes for type INested:
' ...is nested and Public
' ...is AutoLayout
' ...is an interface
' ...is MustInherit
'Attributes for type S:
' ...is not Public
' ...is SequentialLayout
' ...is a value type
' ...is NotInheritable
using System;
using System.Reflection;
internal struct S
{
public int X;
}
public abstract class Example
{
protected sealed class NestedClass {}
public interface INested {}
private static System.Windows.Controls.TextBlock outputBlock;
public static void Demo(System.Windows.Controls.TextBlock outputBlock)
{
Example.outputBlock = outputBlock;
DisplayAttributes(typeof(Example));
DisplayAttributes(typeof(NestedClass));
DisplayAttributes(typeof(INested));
DisplayAttributes(typeof(S));
}
private static void DisplayAttributes(Type t)
{
outputBlock.Text += "Attributes for type "+t.Name+":\n";
TypeAttributes attr = t.Attributes;
// To test for visibility attributes, you must use the visibility
// mask.
TypeAttributes visibility = attr & TypeAttributes.VisibilityMask;
switch (visibility)
{
case TypeAttributes.NotPublic:
outputBlock.Text += " ...is not public\n";
break;
case TypeAttributes.Public:
outputBlock.Text += " ...is public\n";
break;
case TypeAttributes.NestedPublic:
outputBlock.Text += " ...is nested and public\n";
break;
case TypeAttributes.NestedPrivate:
outputBlock.Text += " ...is nested and private\n";
break;
case TypeAttributes.NestedFamANDAssem:
outputBlock.Text += " ...is nested, and inheritable only within the assembly" +
"\n (cannot be declared in C#)\n";
break;
case TypeAttributes.NestedAssembly:
outputBlock.Text += " ...is nested and internal\n";
break;
case TypeAttributes.NestedFamily:
outputBlock.Text += " ...is nested and protected\n";
break;
case TypeAttributes.NestedFamORAssem:
outputBlock.Text += " ...is nested and protected internal\n";
break;
}
TypeAttributes layout = attr & TypeAttributes.LayoutMask;
switch (layout)
{
case TypeAttributes.AutoLayout:
outputBlock.Text += " ...is AutoLayout\n";
break;
case TypeAttributes.SequentialLayout:
outputBlock.Text += " ...is SequentialLayout\n";
break;
case TypeAttributes.ExplicitLayout:
outputBlock.Text += " ...is ExplicitLayout\n";
break;
}
TypeAttributes classSemantics = attr & TypeAttributes.ClassSemanticsMask;
switch (classSemantics)
{
case TypeAttributes.Class:
if (t.IsValueType)
{
outputBlock.Text += " ...is a value type\n";
}
else
{
outputBlock.Text += " ...is a class\n";
}
break;
case TypeAttributes.Interface:
outputBlock.Text += " ...is an interface\n";
break;
}
if (0!=(attr & TypeAttributes.Abstract))
{
outputBlock.Text += " ...is abstract\n";
}
if (0!=(attr & TypeAttributes.Sealed))
{
outputBlock.Text += " ...is sealed\n";
}
}
}
/* This example produces the following output:
Attributes for type Example:
...is public
...is AutoLayout
...is a class
...is abstract
Attributes for type NestedClass:
...is nested and protected
...is AutoLayout
...is a class
...is sealed
Attributes for type INested:
...is nested and public
...is AutoLayout
...is an interface
...is abstract
Attributes for type S:
...is not public
...is SequentialLayout
...is a value type
...is sealed
*/
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
XNA Framework
Supported in: Xbox 360, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.