EventInfo.EventHandlerType 属性

定义

获取与此事件关联的基础事件处理程序委托的 Type 对象。

public:
 virtual property Type ^ EventHandlerType { Type ^ get(); };
public:
 property Type ^ EventHandlerType { Type ^ get(); };
public virtual Type EventHandlerType { get; }
public virtual Type? EventHandlerType { get; }
public Type EventHandlerType { get; }
member this.EventHandlerType : Type
Public Overridable ReadOnly Property EventHandlerType As Type
Public ReadOnly Property EventHandlerType As Type

属性值

表示委托事件处理程序的只读 Type 对象。

实现

例外

调用方没有所要求的权限。

示例

以下示例使用 EventHandlerType 属性来发现事件的委托类型并显示其参数类型。

该示例定义一个名为 的 MyDelegate 委托和一个名为 ev 类型的 MyDelegate事件。 方法中的 Main 代码通过获取事件的委托类型、获取 Invoke 委托类型的 方法,然后检索并显示参数来发现事件签名。

// The following example uses instances of classes in
// the System::Reflection namespace to discover an event argument type.
using namespace System;
using namespace System::Reflection;

public delegate void MyDelegate( int i );
public ref class MainClass
{
public:
   event MyDelegate^ ev;
};

int main()
{
   Type^ delegateType = MainClass::typeid->GetEvent( "ev" )->EventHandlerType;
   MethodInfo^ invoke = delegateType->GetMethod( "Invoke" );
   array<ParameterInfo^>^pars = invoke->GetParameters();
   System::Collections::IEnumerator^ myEnum = pars->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      ParameterInfo^ p = safe_cast<ParameterInfo^>(myEnum->Current);
      Console::WriteLine( p->ParameterType );
   }
}
// The example displays the following output:
//       System.Int32
// The following example uses instances of classes in
// the System.Reflection namespace to discover an event argument type.
using System;
using System.Reflection;

public delegate void MyDelegate(int i);
public class MainClass
{
    public event MyDelegate ev;

    public static void Main()
    {
        Type delegateType = typeof(MainClass).GetEvent("ev").EventHandlerType;
        MethodInfo invoke = delegateType.GetMethod("Invoke");
        ParameterInfo[] pars = invoke.GetParameters();
        foreach (ParameterInfo p in pars)
        {
            Console.WriteLine(p.ParameterType);
        }
    }
}
// The example displays the following output:
//       System.Int32
Imports System.Reflection

Public Delegate Sub MyDelegate(ByVal i As Integer)

Public Class MainClass
    Public Event ev As MyDelegate

    Public Shared Sub Main()
        Dim delegateType As Type = GetType(MainClass).GetEvent("ev").EventHandlerType
        Dim invoke As MethodInfo = delegateType.GetMethod("Invoke")
        Dim pars As ParameterInfo() = invoke.GetParameters()
        For Each p As ParameterInfo In pars
            Console.WriteLine(p.ParameterType)
        Next 
    End Sub 
End Class 
' The example displays the following output:
'     System.Int32

适用于

另请参阅