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Type.GetProperty Method (String)

Searches for the public property with the specified name.

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

'Declaration
Public Function GetProperty ( _
	name As String _
) As PropertyInfo
'Usage
Dim instance As Type
Dim name As String
Dim returnValue As PropertyInfo

returnValue = instance.GetProperty(name)
public final PropertyInfo GetProperty (
	String name
)
public final function GetProperty (
	name : String
) : PropertyInfo
Not applicable.

Parameters

name

The String containing the name of the public property to get.

Return Value

A PropertyInfo object representing the public property with the specified name, if found; otherwise, a null reference (Nothing in Visual Basic).

Exception typeCondition

AmbiguousMatchException

More than one property is found with the specified name. See Remarks.

ArgumentNullException

name is a null reference (Nothing in Visual Basic).

The search for name is case-sensitive. The search includes public static and public instance properties.

If the requested property is non-public and the caller does not have ReflectionPermission to reflect non-public objects outside the current assembly, this method returns a null reference (Nothing in Visual Basic).

A property is considered public to reflection if it has at least one accessor that is public. Otherwise the property is considered private, and you must use BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static (in Visual Basic, combine the values using Or) to get it.

If the current Type represents a constructed generic type, this method returns the PropertyInfo 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 properties of the class constraint.

Situations in which AmbiguousMatchException occurs include the following:

  • A type contains two indexed properties that have the same name but different numbers of parameters. To resolve the ambiguity, use an overload of the GetProperty method that specifies parameter types.

  • A derived type declares a property that hides an inherited property with the same name, by using the new modifier (Shadows in Visual Basic). To resolve the ambiguity, use the GetProperty(String,BindingFlags) method overload and include BindingFlags.DeclaredOnly to restrict the search to members that are not inherited.

Indexers and Default Properties

Visual Basic 2005, Visual C# 2005, and Visual C++ 2005 have simplified syntax for accessing indexed properties and allow one indexed property to be a default for its type. For example, if the variable myList refers to an ArrayList, the syntax myList[3] (myList(3) in Visual Basic) retrieves the element with the index of 3. You can overload the property.

In C#, this feature is called an indexer and cannot be refered to by name. By default, a C# indexer appears in metadata as an indexed property named "Item". However, a class library developer can use the IndexerNameAttribute attribute to change the name of the indexer in the metadata. For example, the String class has an indexer named Chars. Indexed properties created using languages other than C# can have names other than Item, as well. 

To determine whether a type has a default property, use the GetCustomAttributes method to test for the DefaultMemberAttribute attribute. If the type has DefaultMemberAttribute, the MemberName property returns the name of the default property.

The following example retrieves the Type object of a user-defined class, retrieves a property of that class, and displays the property name.

Imports System
Imports System.Reflection
Class MyClass1
    Private myProperty1 As Integer
    ' Declare MyProperty.

    Public Property MyProperty() As Integer
        Get
            Return myProperty1
        End Get
        Set(ByVal Value As Integer)
            myProperty1 = Value
        End Set
    End Property
End Class 'MyClass1

Public Class MyTypeClass
    Public Shared Sub Main(ByVal args() As String)
        Try
            ' Get Type Object corresponding to MyClass.
            Dim myType As Type = GetType(MyClass1)
            ' Get PropertyInfo object by passing property name.
            Dim myPropInfo As PropertyInfo = myType.GetProperty("MyProperty")
            ' Display Name propety to console.
            Console.WriteLine("The {0} property exists in MyClass.", myPropInfo.Name)
        Catch e As NullReferenceException
            Console.WriteLine("The property does not exist in MyClass.", e.Message.ToString())
        End Try
    End Sub 'Main
End Class 'MyTypeClass 

import System.*;
import System.Reflection.*;

class MyClass 
{
    private int myProperty;
    // Declare MyProperty.
   
    /** @property 
     */
    public int get_MyProperty()
    {
        return myProperty ;
    }//MyProperty
    
    /** @property 
     */
    public void set_MyProperty (int value)
    {
        myProperty = value;
    }//MyProperty
} //MyClass

public class MyTypeClass{
   
    public static void main(String[] args)
    {
        try {
            // Get the Type object corresponding to MyClass.
            Type myType = MyClass .class.ToType();
            // Get the PropertyInfo object by passing the property name.
            PropertyInfo myPropInfo = myType.GetProperty("MyProperty");
            // Display the property name.
            Console.WriteLine("The {0} property exists in MyClass.",
                myPropInfo.get_Name());
        }
        catch (NullReferenceException e) {
            Console.WriteLine("The property does not exist in MyClass." 
                + e.get_Message());
        }
    } //main
} //MyTypeClass

Internally, this property is referred to in the metadata by the name "Item." Any attempt to get PropertyInfo using reflection must specify this internal name in order to correctly return the PropertyInfo property.

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

XNA Framework

Supported in: 1.0

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