Type.GetProperty Method (String, Type, Type(), ParameterModifier())

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

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

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

Parameters

name
Type: System.String

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

returnType
Type: System.Type

The return type of the property.

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.

modifiers
Type: System.Reflection.ParameterModifier()

An array of ParameterModifier objects representing the attributes associated with the corresponding element in the types array. The default binder does not process this parameter.

Return Value

Type: System.Reflection.PropertyInfo
An object representing the public property that matches the specified requirements, if found; otherwise, Nothing.

Implements

_Type.GetProperty(String, Type, Type(), ParameterModifier())

ExceptionCondition
AmbiguousMatchException

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

ArgumentNullException

name is Nothing.

-or-

types is Nothing.

ArgumentException

types is multidimensional.

-or-

modifiers is multidimensional.

-or-

types and modifiers do not have the same length.

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.

Although the default binder does not process ParameterModifier (the modifiers parameter), you can use the abstract System.Reflection.Binder class to write a custom binder that does process modifiers. ParameterModifier is only used when calling through COM interop, and only parameters that are passed by reference are handled.

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 obtains a Type object corresponding to MyPropertyClass, and the indexed property of this class is retrieved using the arguments passed to the GetProperty method.

Imports System
Imports System.Reflection

Public Class MyPropertyClass
    Private myPropertyArray(9, 9) As Integer 
    ' Declare an indexer. 
    Default Public Property Item(ByVal i As Integer, ByVal j As Integer) As Integer 
        Get 
            Return myPropertyArray(i, j)
        End Get 
        Set(ByVal Value As Integer)
            myPropertyArray(i, j) = Value
        End Set 
    End Property 
End Class 'MyPropertyClass

Public Class MyTypeClass
    Public Shared Sub Main()
        Try 
            Dim myType As Type = GetType(MyPropertyClass)
            Dim myTypeArray(1) As Type
            ' Create an instance of a Type array representing the number, order  
            ' and type of the parameters for the property.
            myTypeArray.SetValue(GetType(Integer), 0)
            myTypeArray.SetValue(GetType(Integer), 1)
            ' Search for the indexed property whose parameters match the 
            ' specified argument types and modifiers. 
            Dim myPropertyInfo As PropertyInfo = myType.GetProperty("Item", _
                  GetType(Integer), myTypeArray, Nothing)
            Console.WriteLine(myType.FullName + "." + myPropertyInfo.Name + _
                  " has a property  type of " + myPropertyInfo.PropertyType.ToString())
        Catch ex As Exception
            Console.WriteLine("An exception occurred " + ex.Message.ToString())
        End Try 
    End Sub 'Main
End Class 'MyTypeClass

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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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