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Type.GetEvent Method

Definition

Gets a specific event declared or inherited by the current Type.

Overloads

GetEvent(String, BindingFlags)

When overridden in a derived class, returns the EventInfo object representing the specified event, using the specified binding constraints.

GetEvent(String)

Returns the EventInfo object representing the specified public event.

GetEvent(String, BindingFlags)

Source:
Type.cs
Source:
Type.cs
Source:
Type.cs

When overridden in a derived class, returns the EventInfo object representing the specified event, using the specified binding constraints.

public abstract System.Reflection.EventInfo? GetEvent (string name, System.Reflection.BindingFlags bindingAttr);
public abstract System.Reflection.EventInfo GetEvent (string name, System.Reflection.BindingFlags bindingAttr);

Parameters

name
String

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

bindingAttr
BindingFlags

A bitwise combination of the enumeration values that specify how the search is conducted.

-or-

Default to return null.

Returns

The object representing the specified event that is declared or inherited by the current Type, if found; otherwise, null.

Implements

Exceptions

name is null.

Examples

The following code example uses the GetEvent(String, BindingFlags) method to search a type for a public or non-public event named "Click" that is not static (Shared in Visual Basic).

using System;
using System.Reflection;
using System.Security;

class MyEventExample
{
    public static void Main()
    {
        try
        {

            // Creates a bitmask based on BindingFlags.
            BindingFlags myBindingFlags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic;
            Type myTypeBindingFlags = typeof(System.Windows.Forms.Button);
            EventInfo myEventBindingFlags = myTypeBindingFlags.GetEvent("Click", myBindingFlags);
            if(myEventBindingFlags != null)
            {
                Console.WriteLine("Looking for the Click event in the Button class with the specified BindingFlags.");
                Console.WriteLine(myEventBindingFlags.ToString());
            }
            else
            {
                Console.WriteLine("The Click event is not available with the Button class.");
            }
        }
        catch(SecurityException e)
        {
            Console.WriteLine("An exception occurred.");
            Console.WriteLine("Message :"+e.Message);
        }
        catch(ArgumentNullException e)
        {
            Console.WriteLine("An exception occurred.");
            Console.WriteLine("Message :"+e.Message);
        }
        catch(Exception e)
        {
            Console.WriteLine("The following exception was raised : {0}",e.Message);
        }
    }
}

Remarks

The following BindingFlags filter flags can be used to define which events to include in the search:

  • You must specify either BindingFlags.Instance or BindingFlags.Static in order to get a return.

  • Specify BindingFlags.Public to include public events in the search.

  • Specify BindingFlags.NonPublic to include non-public events (that is, private, internal, and protected events) in the search.

  • Specify BindingFlags.FlattenHierarchy to include public and protected static members up the hierarchy; private static members in inherited classes are not included.

The following BindingFlags modifier flags can be used to change how the search works:

  • BindingFlags.IgnoreCase to ignore the case of name.

  • BindingFlags.DeclaredOnly to search only the events declared on the Type, not events that were simply inherited.

See System.Reflection.BindingFlags for more information.

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.

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.

See also

Applies to

.NET 9 и другие версии
Продукт Версии
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

GetEvent(String)

Source:
Type.cs
Source:
Type.cs
Source:
Type.cs

Returns the EventInfo object representing the specified public event.

public System.Reflection.EventInfo? GetEvent (string name);
public System.Reflection.EventInfo GetEvent (string name);

Parameters

name
String

The string containing the name of an event that is declared or inherited by the current Type.

Returns

The object representing the specified public event that is declared or inherited by the current Type, if found; otherwise, null.

Implements

Exceptions

name is null.

Examples

The following example creates an EventInfo object and gets the event for a button class for the specified event.

using System;
using System.Reflection;
using System.Security;

class MyEventExample
{
    public static void Main()
    {
        try
        {

            Type myType = typeof(System.Windows.Forms.Button);
            EventInfo myEvent = myType.GetEvent("Click");
            if(myEvent != null)
            {
                Console.WriteLine("Looking for the Click event in the Button class.");
                Console.WriteLine(myEvent.ToString());
            }
            else
            {
                Console.WriteLine("The Click event is not available in the Button class.");
            }
        }
        catch(SecurityException e)
        {
            Console.WriteLine("An exception occurred.");
            Console.WriteLine("Message :"+e.Message);
        }
        catch(ArgumentNullException e)
        {
            Console.WriteLine("An exception occurred.");
            Console.WriteLine("Message :"+e.Message);
        }
        catch(Exception e)
        {
            Console.WriteLine("The following exception was raised : {0}",e.Message);
        }
    }
}

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.
  1. 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.

  2. 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.

  3. 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.

See also

Applies to

.NET 9 и другие версии
Продукт Версии
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1