Updated: September 2009
Searches for the public property with the specified name.
Namespace:
System
Assembly:
mscorlib (in mscorlib.dll)
Visual Basic (Declaration)
Public Function GetProperty ( _
name As String _
) As PropertyInfo
Dim instance As Type
Dim name As String
Dim returnValue As PropertyInfo
returnValue = instance.GetProperty(name)
public PropertyInfo GetProperty(
string name
)
public:
virtual PropertyInfo^ GetProperty(
String^ name
) sealed
public final function GetProperty(
name : String
) : PropertyInfo
Implements
_Type..::.GetProperty(String)
The search for name is case-sensitive. The search includes public static and public instance properties.
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(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 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
using System;
using System.Reflection;
class MyClass
{
private int myProperty;
// Declare MyProperty.
public int MyProperty
{
get
{
return myProperty;
}
set
{
myProperty=value;
}
}
}
public class MyTypeClass
{
public static void Main(string[] args)
{
try
{
// Get the Type object corresponding to MyClass.
Type myType=typeof(MyClass);
// 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.Name);
}
catch(NullReferenceException e)
{
Console.WriteLine("The property does not exist in MyClass." + e.Message);
}
}
}
using namespace System;
using namespace System::Reflection;
ref class MyClass
{
private:
int myProperty;
public:
property int MyProperty
{
// Declare MyProperty.
int get()
{
return myProperty;
}
void set( int value )
{
myProperty = value;
}
}
};
int main()
{
try
{
// Get the Type object corresponding to MyClass.
Type^ myType = MyClass::typeid;
// 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->Name );
}
catch ( NullReferenceException^ e )
{
Console::WriteLine( "The property does not exist in MyClass. {0}", e->Message );
}
}
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 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
Reference
Date | History | Reason |
|---|
September 2009
| Removed an erroneous statement that nullNothingnullptra null reference (Nothing in Visual Basic) is returned for non-public members outside the assembly, if caller lacks ReflectionPermission. |
Content bug fix.
|