Artículo
11/17/2011

Type.GetEvent Method (String)

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Returns the EventInfo object representing the specified public event.

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

Syntax

'Declaration
Public Function GetEvent ( _
    name As String _
) As EventInfo

public EventInfo GetEvent(
    string name
)

Parameters

name
Type: System.String
The String containing the name of an event which is declared or inherited by the current Type.

Return Value

Type: System.Reflection.EventInfo
The EventInfo object representing the specified public event which is declared or inherited by the current Type, if found; otherwise, nulla null reference (Nothing in Visual Basic).

Exceptions

Exception	Condition
ArgumentNullException	name is nulla null reference (Nothing in Visual Basic).

Remarks

An event is considered public to reflection if it has at least one method or accessor that is public. Otherwise the event 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 events.

The following table shows what members of a base class are returned by the Get methods when reflecting on a type.

Member Type	Static	Non-Static
Constructor	No	No
Field	No	Yes. A field is always hide-by-name-and-signature.
Event	Not applicable	The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.
Method	No	Yes. A method (both virtual and non-virtual) can be hide-by-name or hide-by-name-and-signature.
Nested Type	No	No
Property	Not applicable	The common type system rule is that the inheritance is the same as that of the methods that implement the property. Reflection treats properties as hide-by-name-and-signature. See note 2 below.

Notes:

Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. This is a binary comparison.
For reflection, properties and events are hide-by-name-and-signature. If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.
Custom attributes are not part of the common type system.

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

Examples

The following example gets an EventInfo object for a specified event.

Note:
To run this example, see Building Examples That Use a Demo Method and a TextBlock Control.

Imports System.Reflection

Class Example

    Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)

        Dim myType As Type = outputBlock.GetType()

        Dim myEvent As EventInfo = myType.GetEvent("MouseLeftButtonUp")

        If Not (myEvent Is Nothing) Then
            outputBlock.Text &= "Looking for the MouseLeftButtonUp event in the " & _
                myType.FullName & " class." & vbCrLf
            outputBlock.Text &= myEvent.ToString() & vbCrLf
        Else
            outputBlock.Text &= "The MouseLeftButtonUp event is not found in the " & _
                myType.FullName & " class." & vbCrLf
        End If

   End Sub 
End Class 

' This example produces the following output:
'
'Looking for the MouseLeftButtonUp event in the System.Windows.Controls.TextBlock class.
'System.Windows.Input.MouseButtonEventHandler MouseLeftButtonUp

using System.Reflection;
using System;

class Example
{
    public static void Demo(System.Windows.Controls.TextBlock outputBlock)
    {
        Type myType = outputBlock.GetType();

        EventInfo myEvent = myType.GetEvent("MouseLeftButtonUp");

        if (myEvent != null)
        {
            outputBlock.Text += "Looking for the MouseLeftButtonUp event in the " +
                myType.FullName + " class.\n";
            outputBlock.Text += myEvent.ToString() + "\n";
        }
        else
        {
            outputBlock.Text += "The MouseLeftButtonUp event is not found in the " +
                myType.FullName + " class.\r\n";
        }
    }
}

/* This example produces the following output:

Looking for the MouseLeftButtonUp event in the System.Windows.Controls.TextBlock class.
System.Windows.Input.MouseButtonEventHandler MouseLeftButtonUp
 */

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.

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