FieldAttributes Enumeration

Definition

public enum class FieldAttributes

[System.Flags]
public enum FieldAttributes

[System.Flags]
[System.Serializable]
public enum FieldAttributes

[System.Flags]
[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public enum FieldAttributes

[<System.Flags>]
type FieldAttributes = 

[<System.Flags>]
[<System.Serializable>]
type FieldAttributes = 

[<System.Flags>]
[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type FieldAttributes = 

Public Enum FieldAttributes

Vererbung

Object

ValueType

Enum

FieldAttributes

Attribute

FlagsAttribute SerializableAttribute ComVisibleAttribute

Felder

Beispiele

In diesem Beispiel werden drei Felder erstellt, und die FieldAttributes Werte werden angezeigt. Ein FieldAttributes Wert kann mehr als ein Attribut enthalten, z. B. sowohl als Literalauch Public , wie im dritten Feld dargestellt.

using namespace System;
using namespace System::Reflection;
using namespace System::Security::Permissions;

public ref class Demo
{
private:
    // Make three fields:
    // The first field is private.
    String^ m_field;

    // The second field is public.
public:
    String^ Field;

    // The third field is public and literal. 
    literal String^ FieldC = "String C";

    Demo() { m_field = "String A"; Field = "String B"; }
};

static void DisplayField(Object^ obj, FieldInfo^ f)
{ 
    // Display the field name, value, and attributes.
    //
    Console::WriteLine("{0} = \"{1}\"; attributes: {2}", 
        f->Name, f->GetValue(obj), f->Attributes);
};

void main()
{
    Console::WriteLine ("\nReflection.FieldAttributes");
    Demo^ d = gcnew Demo();

    // Get a Type object for Demo, and a FieldInfo for each of
    // the three fields. Use the FieldInfo to display field
    // name, value for the Demo object in d, and attributes.
    //
    Type^ myType = Demo::typeid;

    FieldInfo^ fiPrivate = myType->GetField("m_field",
        BindingFlags::NonPublic | BindingFlags::Instance);
    DisplayField(d, fiPrivate);

    FieldInfo^ fiPublic = myType->GetField("Field",
        BindingFlags::Public | BindingFlags::Instance);
    DisplayField(d, fiPublic);

    FieldInfo^ fiConstant = myType->GetField("FieldC",
        BindingFlags::Public | BindingFlags::Static);
    DisplayField(d, fiConstant);
}

/* This code example produces the following output:

Reflection.FieldAttributes
m_field = "String A"; attributes: Private
Field = "String B"; attributes: Public
FieldC = "String C"; attributes: Public, Static, Literal, HasDefault
 */

using System;
using System.Reflection;

public class Demo
{
    // Make three fields:
    // The first field is private.
    private string m_field = "String A";

    // The second field is public.
    public string Field = "String B";

    // The third field is public const (hence also literal and static),
    // with a default value.
    public const string FieldC = "String C";
}

public class Myfieldattributes
{
    public static void Main()
    {
        Console.WriteLine ("\nReflection.FieldAttributes");
        Demo d = new Demo();

        // Get a Type object for Demo, and a FieldInfo for each of
        // the three fields. Use the FieldInfo to display field
        // name, value for the Demo object in d, and attributes.
        //
        Type myType = typeof(Demo);
        FieldInfo fiPrivate = myType.GetField("m_field",
            BindingFlags.NonPublic | BindingFlags.Instance);
        DisplayField(d, fiPrivate);

        FieldInfo fiPublic = myType.GetField("Field",
            BindingFlags.Public | BindingFlags.Instance);
        DisplayField(d, fiPublic);

        FieldInfo fiConstant = myType.GetField("FieldC",
            BindingFlags.Public | BindingFlags.Static);
        DisplayField(d, fiConstant);
    }

    static void DisplayField(Object obj, FieldInfo f)
    {
        // Display the field name, value, and attributes.
        //
        Console.WriteLine("{0} = \"{1}\"; attributes: {2}",
            f.Name, f.GetValue(obj), f.Attributes);
    }
}

/* This code example produces the following output:

Reflection.FieldAttributes
m_field = "String A"; attributes: Private
Field = "String B"; attributes: Public
FieldC = "String C"; attributes: Public, Static, Literal, HasDefault
 */

Imports System.Reflection

Public Class Demo
    ' Declare three fields.
    ' The first field is private.
    Private m_field As String = "String A"

    'The second field is public.
    Public Field As String = "String B"

    ' The third field is public and const, hence also static
    ' and literal with a default value.
    Public Const FieldC As String = "String C"

End Class

Module Module1
    Sub Main()
        ' Create an instance of the Demo class.
        Dim d As New Demo()

        Console.WriteLine(vbCrLf & "Reflection.FieldAttributes")

        ' Get a Type object for Demo, and a FieldInfo for each of
        ' the three fields. Use the FieldInfo to display field
        ' name, value for the Demo object in d, and attributes.
        '
        Dim myType As Type = GetType(Demo)

        Dim fiPrivate As FieldInfo = myType.GetField("m_field", _
            BindingFlags.NonPublic Or BindingFlags.Instance)
        DisplayField(d, fiPrivate)

        Dim fiPublic As FieldInfo = myType.GetField("Field", _
            BindingFlags.Public Or BindingFlags.Instance)
        DisplayField(d, fiPublic)

        Dim fiConstant As FieldInfo = myType.GetField("FieldC", _
            BindingFlags.Public Or BindingFlags.Static)
        DisplayField(d, fiConstant)
    End Sub

    Sub DisplayField(ByVal obj As Object, ByVal f As FieldInfo)

        ' Display the field name, value, and attributes.
        '
        Console.WriteLine("{0} = ""{1}""; attributes: {2}", _
            f.Name, f.GetValue(obj), f.Attributes)
    End Sub

End Module

' This code example produces the following output:
'
'm_field = "String A"; attributes: Private
'Field = "String B"; attributes: Public
'FieldC = "String C"; attributes: Public, Static, Literal, HasDefault

Hinweise

FieldAttributes verwendet den Wert von FieldAccessMask , um nur die Teile des Attributwerts zu maskieren, die sich auf die Barrierefreiheit beziehen. Der folgende Code bestimmt beispielsweise, ob Attributes das öffentliche Bit festgelegt ist.

FieldInfo^ fi = obj->GetType()->GetField("field1");

if ((fi->Attributes & FieldAttributes::FieldAccessMask) ==
    FieldAttributes::Public)
{
    Console::WriteLine("{0:s} is public. Value: {1:d}", fi->Name, fi->GetValue(obj));
}

FieldInfo fi = obj.GetType().GetField("field1");

if ((fi.Attributes & FieldAttributes.FieldAccessMask) ==
    FieldAttributes.Public)
{
    Console.WriteLine("{0:s} is public. Value: {1:d}", fi.Name, fi.GetValue(obj));
}

Dim fi As FieldInfo = obj.GetType().GetField("field1")

If (fi.Attributes And FieldAttributes.FieldAccessMask) = _
    FieldAttributes.Public Then
    Console.WriteLine("{0:s} is public. Value: {1:d}", fi.Name, fi.GetValue(obj))
End If

Um die FieldAttributesabzurufen, rufen Sie zuerst die -Klasse Typeab. Rufen Sie FieldInfovon abType. Rufen Sie Attributesvon abFieldInfo.

Der aufgezählte Wert ist eine Zahl, die das bitweise OR der attribute darstellt, die im Feld implementiert sind.

Gilt für: