Статья
11/18/2011

Type.GetFields Method

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Returns all the public fields of the current Type.

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

Syntax

'Declaration
Public Function GetFields As FieldInfo()

public FieldInfo[] GetFields()

Return Value

Type: array<System.Reflection.FieldInfo[]
An array of FieldInfo objects representing all the public fields defined for the current Type.
-or-
An empty array of type FieldInfo, if no public fields are defined for the current Type.

Remarks

The GetFields method does not return fields in a particular order, such as alphabetical or declaration order. Your code must not depend on the order in which fields are returned, because that order varies.

The following table shows what members of a base class are returned by the Get methods when reflecting on a type.

Member Type	Static	Non-Static
Constructor	No	No
Field	No	Yes. A field is always hide-by-name-and-signature.
Event	Not applicable	The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.
Method	No	Yes. A method (both virtual and non-virtual) can be hide-by-name or hide-by-name-and-signature.
Nested Type	No	No
Property	Not applicable	The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.

Notes:

Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. This is a binary comparison.
For reflection, properties and events are hide-by-name-and-signature. If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.
Custom attributes are not part of the common type system.

If the current Type represents a constructed generic type, this method returns the FieldInfo objects with the type parameters replaced by the appropriate type arguments.

If the current Type represents a type parameter in the definition of a generic type or generic method, this method searches the public fields of the class constraint.

Examples

The following example shows a use of the GetFields() method.

Note:
To run this example, see Building Examples That Use a Demo Method and a TextBlock Control.

Imports System.Reflection

Class Example

    Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

        Dim myType As Type = GetType(EventAttributes)

        outputBlock.Text = _
            String.Format("Fields of {0}, flagging FieldAttributes.SpecialName:" & vbLf, _
                          myType.Name)

        For Each fi As FieldInfo in myType.GetFields()
            ' Determine whether or not each field has a special name.
            If fi.IsSpecialName Then
                outputBlock.Text &= _
                    String.Format("{0} has the FieldAttributes.SpecialName attribute." & vbLf, _
                                  fi.Name)
            Else
                outputBlock.Text &= fi.Name & vbLf
            End If
        Next fi

    End Sub 

End Class 

' This example produces output similar to the following:
'
'Fields of EventAttributes, flagging FieldAttributes.SpecialName:
'value__ has the FieldAttributes.SpecialName attribute.
'None
'SpecialName
'ReservedMask
'RTSpecialName

using System;
using System.Reflection;

class Example
{
    public static void Demo(System.Windows.Controls.TextBlock outputBlock)
    {
        Type myType = typeof(EventAttributes);

        outputBlock.Text = 
            String.Format("Fields of {0}, flagging FieldAttributes.SpecialName:\n",
                          myType.Name);

        foreach (FieldInfo fi in myType.GetFields())
        {
            // Determine whether or not each field has a special name.
            if (fi.IsSpecialName)
            {
                outputBlock.Text += 
                    String.Format("{0} has the FieldAttributes.SpecialName attribute.\n", 
                                  fi.Name);
            }
            else
            {
                outputBlock.Text += fi.Name + "\n";
            }
        }
    }
}

/* This example produces output similar to the following:

Fields of EventAttributes, flagging FieldAttributes.SpecialName:
value__ has the FieldAttributes.SpecialName attribute.
None
SpecialName
ReservedMask
RTSpecialName
 */

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.

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