EventInfo Class

July 28, 2014

Discovers the attributes of an event and provides access to event metadata.

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

'Declaration
Public MustInherit Class EventInfo _
	Inherits MemberInfo

The EventInfo type exposes the following members.

  NameDescription
Public propertyAddMethodGets the MethodInfo object for the AddEventHandler method of the event, including non-public methods.
Public propertyAttributesGets the attributes for this event.
Public propertyCustomAttributesGets a collection that contains this member's custom attributes. (Inherited from MemberInfo.)
Public propertyDeclaringTypeGets the class that declares this member. (Inherited from MemberInfo.)
Public propertyEventHandlerTypeGets the Type object of the underlying event-handler delegate associated with this event.
Public propertyIsMulticastGets a value that indicates whether the event is multicast.
Public propertyIsSpecialNameGets a value that indicates whether the EventInfo has a name with a special meaning.
Public propertyMemberTypeGets a MemberTypes value indicating that this member is an event. (Overrides MemberInfo.MemberType.)
Public propertyMetadataTokenGets a value that identifies a metadata element. (Inherited from MemberInfo.)
Public propertyModuleGets the module in which the type that declares the member represented by the current MemberInfo is defined. (Inherited from MemberInfo.)
Public propertyNameGets the name of the current member. (Inherited from MemberInfo.)
Public propertyRaiseMethodGets the method that is called when the event is raised, including non-public methods.
Public propertyReflectedTypeGets the class object that was used to obtain this instance of MemberInfo. (Inherited from MemberInfo.)
Public propertyRemoveMethodGets the MethodInfo object for removing a method of the event, including non-public methods.
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  NameDescription
Public methodAddEventHandlerAdds an event handler to an event source.
Public methodEqualsReturns a value that indicates whether this instance is equal to a specified object. (Overrides MemberInfo.Equals(Object).)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetAddMethodReturns the method that is used to add an event-handler delegate to the event source.
Public methodGetAddMethod(Boolean)When overridden in a derived class, returns the method that is used to add an event-handler delegate to the event source, specifying whether to return the method if the current event is non-public.
Public methodGetCustomAttributes(Boolean)When overridden in a derived class, returns an array of all custom attributes applied to this member. (Inherited from MemberInfo.)
Public methodGetCustomAttributes(Type, Boolean)When overridden in a derived class, returns an array of custom attributes applied to this member and identified by Type. (Inherited from MemberInfo.)
Public methodGetHashCodeReturns the hash code for this instance. (Overrides MemberInfo.GetHashCode.)
Public methodGetRaiseMethodReturns the method that is called when the event is raised.
Public methodGetRaiseMethod(Boolean)When overridden in a derived class, returns the method that is called when the event is raised, specifying whether to return non-public methods.
Public methodGetRemoveMethodReturns the method that is used to remove an event-handler delegate from the event source.
Public methodGetRemoveMethod(Boolean)When overridden in a derived class, retrieves the MethodInfo object for removing a method of the event, specifying whether to return non-public methods.
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodIsDefinedWhen overridden in a derived class, indicates whether one or more attributes of the specified type or of its derived types is applied to this member. (Inherited from MemberInfo.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Public methodRemoveEventHandlerRemoves an event handler from an event source.
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)
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  NameDescription
Public Extension MethodGetCustomAttribute(Type)Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member. (Defined by CustomAttributeExtensions.)
Public Extension MethodGetCustomAttribute(Type, Boolean)Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member, and optionally inspects the ancestors of that member. (Defined by CustomAttributeExtensions.)
Public Extension MethodGetCustomAttribute(Of T)Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member. (Defined by CustomAttributeExtensions.)
Public Extension MethodGetCustomAttribute(Of T)(Boolean)Overloaded. Retrieves a custom attribute of a specified type that is applied to a specified member, and optionally inspects the ancestors of that member. (Defined by CustomAttributeExtensions.)
Public Extension MethodGetCustomAttributesOverloaded. Retrieves a collection of custom attributes that are applied to a specified member. (Defined by CustomAttributeExtensions.)
Public Extension MethodGetCustomAttributes(Type)Overloaded. Retrieves a collection of custom attributes of a specified type that are applied to a specified member. (Defined by CustomAttributeExtensions.)
Public Extension MethodGetCustomAttributes(Of T)Overloaded. Retrieves a collection of custom attributes of a specified type that are applied to a specified member. (Defined by CustomAttributeExtensions.)
Public Extension MethodGetCustomAttributes(Of T)(Boolean)Overloaded. Retrieves a collection of custom attributes of a specified type that are applied to a specified member, and optionally inspects the ancestors of that member. (Defined by CustomAttributeExtensions.)
Public Extension MethodIsDefinedIndicates whether custom attributes of a specified type are applied to a specified member. (Defined by CustomAttributeExtensions.)
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Use the EventInfo class to inspect events and to hook up event handlers, as shown in the example code for the AddEventHandler method.

NoteNote:

EventInfo is not intended to be used to raise events. An object raises events as dictated by its internal state.

Calling ICustomAttributeProvider.GetCustomAttributes on EventInfo when the inherit parameter of GetCustomAttributes is true does not walk the type hierarchy. You can use System.Attribute to walk the type hierarchy for custom attributes, but only if all the attributes derive from System.Attribute.

In Windows Phone, you cannot inherit from EventInfo.

The following code gets an EventInfo object for the MouseLeftButtonUp event of 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", _
            BindingFlags.Instance Or BindingFlags.Public)

        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


Windows Phone OS

Supported in: 8.1, 8.0, 7.1, 7.0

Windows Phone

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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