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Type.GetProperty Method (String, Type())

Searches for the specified public property whose parameters match the specified argument types.

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

'Declaration
Public Function GetProperty ( _
	name As String, _
	types As Type() _
) As PropertyInfo

Parameters

name
Type: System.String
The string containing the name of the public property to get.
types
Type: System.Type()
An array of Type objects representing the number, order, and type of the parameters for the indexed property to get.
-or-
An empty array of the type Type (that is, Type[] types = new Type[0]) to get a property that is not indexed.

Return Value

Type: System.Reflection.PropertyInfo
An object representing the public property whose parameters match the specified argument types, if found; otherwise, Nothing.

Implements

_Type.GetProperty(String, Type())

ExceptionCondition
AmbiguousMatchException

More than one property is found with the specified name and matching the specified argument types.

ArgumentNullException

name is Nothing.

-or-

types is Nothing.

ArgumentException

types is multidimensional.

NullReferenceException

An element of types is Nothing.

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.

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

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.

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(Type, Boolean) 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 the property of that class, and displays the property name and type of the property as specified by the arguments passed to GetProperty.


Imports System
Imports System.Reflection

Module Module1
    Class MyClass1
        Private myArray As Integer(,) = {{1, 2}, {3, 4}}
        ' Declare an indexer.
        Default Public Property Item(ByVal i As Integer, ByVal j As Integer) As Integer
            Get
                Return myArray(i, j)
            End Get
            Set(ByVal Value As Integer)

                myArray(i, j) = Value
            End Set
        End Property
    End Class 'MyClass1

    Public Class MyTypeClass
        Public Shared Sub Main()
            Try
                ' Get the Type Object.
                Dim myType As Type = GetType(MyClass1)
                Dim myTypeArr(1) As Type
                ' Create an instance of a Type array.
                myTypeArr.SetValue(GetType(Integer), 0)
                myTypeArr.SetValue(GetType(Integer), 1)
                ' Get the PropertyInfo object for the indexed property Item, which has two integer parameters. 
                Dim myPropInfo As PropertyInfo = myType.GetProperty("Item", myTypeArr)
                ' Display the property.
                Console.WriteLine("The {0} property exists in MyClass1.", myPropInfo.ToString())
            Catch e As NullReferenceException
                Console.WriteLine("An exception occurred.")
                Console.WriteLine("Source : {0}", e.Source.ToString())
                Console.WriteLine("Message : {0}", e.Message.ToString())
            End Try
        End Sub 'Main
    End Class 'MyTypeClass
End Module 'Module1


.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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

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