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FieldInfo Class

Discovers the attributes of a field and provides access to field metadata.

Namespace:  System.Reflection
Assembly:  mscorlib (in mscorlib.dll)

'Declaration
<SerializableAttribute> _
<ComVisibleAttribute(True)> _
<ClassInterfaceAttribute(ClassInterfaceType.None)> _
<PermissionSetAttribute(SecurityAction.InheritanceDemand, Name := "FullTrust")> _
Public MustInherit Class FieldInfo _
	Inherits MemberInfo _
	Implements _FieldInfo
'Usage
Dim instance As FieldInfo

The field information is obtained from metadata. The FieldInfo class does not have a public constructor. FieldInfo objects are obtained by calling either the GetFields or GetField method of a Type object.

Fields are variables defined in the class. FieldInfo provides access to the metadata for a field within a class and provides dynamic set and get functionality for the field. The class is not loaded into memory until invoke or get is called on the object.

Notes to Inheritors:

When you inherit from FieldInfo, you must override the following members: GetValue and SetValue.

The following example uses the Type.GetFields method to get the field-related information from the FieldInfo class, and then displays field attributes.

Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic

Public Class FieldInfoClass
    Public myField1 As Integer = 0
    Protected myField2 As String = Nothing 

    Public Shared Sub Main()
        Dim myFieldInfo() As FieldInfo
        Dim myType As Type = GetType(FieldInfoClass)
        ' Get the type and fields of FieldInfoClass.
        myFieldInfo = myType.GetFields(BindingFlags.NonPublic Or _
                      BindingFlags.Instance Or BindingFlags.Public)
        Console.WriteLine(ControlChars.NewLine & "The fields of " & _
                      "FieldInfoClass class are " & ControlChars.NewLine)
        ' Display the field information of FieldInfoClass. 
        Dim i As Integer 
        For i = 0 To myFieldInfo.Length - 1
            Console.WriteLine(ControlChars.NewLine + "Name            : {0}", myFieldInfo(i).Name)
            Console.WriteLine("Declaring Type  : {0}", myFieldInfo(i).DeclaringType)
            Console.WriteLine("IsPublic        : {0}", myFieldInfo(i).IsPublic)
            Console.WriteLine("MemberType      : {0}", myFieldInfo(i).MemberType)
            Console.WriteLine("FieldType       : {0}", myFieldInfo(i).FieldType)
            Console.WriteLine("IsFamily        : {0}", myFieldInfo(i).IsFamily)
        Next i
    End Sub 
End Class

This type is thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

XNA Framework

Supported in: 3.0, 2.0, 1.0
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