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Type.GetProperty Method (String, Type)

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Searches for the public property with the specified name and return type.

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

Syntax

'Declaration
Public Function GetProperty ( _
    name As String, _
    returnType As Type _
) As PropertyInfo
public PropertyInfo GetProperty(
    string name,
    Type returnType
)

Parameters

  • returnType
    Type: System.Type
    The return type of the property.

Return Value

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

Exceptions

Exception Condition
AmbiguousMatchException

More than one property is found with the specified name.

ArgumentNullException

name is nulla null reference (Nothing in Visual Basic), or returnType is nulla null reference (Nothing in Visual Basic).

Remarks

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 a List<T>, 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.

Examples

The following example defines a class with one property and retrieves the name and type of the property.

Imports System.Reflection
Class MyClass1
   Private myMessage As [String] = "Hello World."
   Public Property MyProperty1() As String
      Get
         Return myMessage
      End Get
      Set(ByVal Value As String)
         myMessage = Value
      End Set
   End Property
End Class 'MyClass1

Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      Try
         Dim myType As Type = GetType(MyClass1)
         ' Get the PropertyInfo object representing MyProperty1. 
         Dim myStringProperties1 As PropertyInfo = myType.GetProperty("MyProperty1", GetType(String))
         outputBlock.Text += String.Format("The name of the first property of MyClass1 is {0}.", myStringProperties1.Name) & vbCrLf
         outputBlock.Text += String.Format("The type of the first property of MyClass1 is {0}.", myStringProperties1.PropertyType.ToString()) & vbCrLf
      Catch e As ArgumentNullException
         outputBlock.Text &= "ArgumentNullException :" + e.Message.ToString() & vbCrLf
      Catch e As AmbiguousMatchException
         outputBlock.Text &= "AmbiguousMatchException :" + e.Message.ToString() & vbCrLf
      Catch e As NullReferenceException
         outputBlock.Text += String.Format("Message : {0}", e.Message.ToString()) & vbCrLf
      End Try
      'Output:
      'The name of the first property of MyClass1 is MyProperty1.
      'The type of the first property of MyClass1 is System.String.
   End Sub 'Main
End Class 'TestClass

using System;
using System.Reflection;

class MyClass1
{
   String myMessage = "Hello World.";
   public string MyProperty1
   {
      get
      {
         return myMessage;
      }
      set
      {
         myMessage = value;
      }
   }
}
class Example
{
   public static void Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      try
      {
         Type myType = typeof(MyClass1);
         // Get the PropertyInfo object representing MyProperty1. 
         PropertyInfo myStringProperties1 = myType.GetProperty("MyProperty1",
             typeof(string));
         outputBlock.Text += String.Format("The name of the first property of MyClass1 is {0}.", myStringProperties1.Name) + "\n";
         outputBlock.Text += String.Format("The type of the first property of MyClass1 is {0}.", myStringProperties1.PropertyType) + "\n";
      }
      catch (ArgumentNullException e)
      {
         outputBlock.Text += "ArgumentNullException :" + e.Message + "\n";

      }
      catch (AmbiguousMatchException e)
      {
         outputBlock.Text += "AmbiguousMatchException :" + e.Message + "\n";
      }
      catch (NullReferenceException e)
      {
         outputBlock.Text += String.Format("Message : {0}", e.Message) + "\n";
      }
      //Output:
      //The name of the first property of MyClass1 is MyProperty1.
      //The type of the first property of MyClass1 is System.String.

   }
}

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.