Type.FilterAttribute 字段

定义

表示用在特性上的成员筛选器。Represents the member filter used on attributes. 此字段为只读。This field is read-only.

public: static initonly System::Reflection::MemberFilter ^ FilterAttribute;
public static readonly System.Reflection.MemberFilter FilterAttribute;
 staticval mutable FilterAttribute : System.Reflection.MemberFilter
Public Shared ReadOnly FilterAttribute As MemberFilter 

字段值

示例

下面的示例获取 FilterAttribute 委托,将其作为参数传递到 FindMembers 方法,并显示指定的成员及其属性。The following example gets the FilterAttribute delegate, passes it as a parameter to the FindMembers method, and displays the specified members and their attributes.

using namespace System;
using namespace System::Collections;
using namespace System::Reflection;
using namespace System::Security;
int main()
{
   try
   {
      MemberFilter^ myFilter = Type::FilterAttribute;
      Type^ myType = System::String::typeid;
      array<MemberInfo^>^myMemberInfoArray = myType->FindMembers( static_cast<MemberTypes>(MemberTypes::Constructor | MemberTypes::Method), static_cast<BindingFlags>(BindingFlags::Public | BindingFlags::Static | BindingFlags::Instance), myFilter, MethodAttributes::SpecialName );
      IEnumerator^ myEnum = myMemberInfoArray->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         MemberInfo^ myMemberinfo = safe_cast<MemberInfo^>(myEnum->Current);
         Console::Write( "\n {0}", myMemberinfo->Name );
         Console::Write( " is a {0}", myMemberinfo->MemberType );
      }
   }
   catch ( ArgumentNullException^ e ) 
   {
      Console::Write( "ArgumentNullException : {0}", e->Message );
   }
   catch ( SecurityException^ e ) 
   {
      Console::Write( "SecurityException : {0}", e->Message );
   }
   catch ( Exception^ e ) 
   {
      Console::Write( "Exception : {0}", e->Message );
   }

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

public class MyFilterAttributeSample
{
    public static void Main()
    {
        try
        {
            MemberFilter myFilter = Type.FilterAttribute;
            Type myType = typeof(System.String);
            MemberInfo[] myMemberInfoArray = myType.FindMembers(MemberTypes.Constructor
                |MemberTypes.Method, BindingFlags.Public | BindingFlags.Static |
                BindingFlags.Instance, myFilter, MethodAttributes.SpecialName);
            foreach (MemberInfo myMemberinfo in myMemberInfoArray) 
            { 
                Console.Write ("\n" + myMemberinfo.Name);
                Console.Write (" is a " + myMemberinfo.MemberType.ToString()); 
            }
        }
        catch(ArgumentNullException e)
        {
            Console.Write("ArgumentNullException : " + e.Message); 
        }   
        catch(SecurityException e)
        {
            Console.Write("SecurityException : " + e.Message); 
        }   
        catch(Exception e)
        {
            Console.Write("Exception :" + e.Message); 
        } 
    }	
}
Imports System.Reflection
Imports System.Security

Public Class MyFilterAttributeSample

    Public Shared Sub Main()
        Try
            Dim myFilter As MemberFilter = Type.FilterAttribute
            Dim myType As Type = GetType(System.String)
            Dim myMemberInfoArray As MemberInfo() = myType.FindMembers(MemberTypes.Constructor Or MemberTypes.Method, BindingFlags.Public Or BindingFlags.Static Or BindingFlags.Instance, myFilter, MethodAttributes.SpecialName)
            Dim myMemberinfo As MemberInfo
            For Each myMemberinfo In myMemberInfoArray
                Console.Write(ControlChars.newline + myMemberinfo.Name)
                Console.Write(" is a " + myMemberinfo.MemberType.ToString())
            Next myMemberinfo

        Catch e As ArgumentNullException
            Console.Write("ArgumentNullException : " + e.Message.ToString())
        Catch e As SecurityException
            Console.Write("SecurityException : " + e.Message.ToString())
        Catch e As Exception
            Console.Write("Exception :" + e.Message.ToString())
        End Try
    End Sub
End Class

注解

此字段保存对 FindMembers 方法使用的委托的引用。This field holds a reference to the delegate used by the FindMembers method. 此委托封装的方法采用两个参数:第一个是 MemberInfo 对象,第二个参数是 ObjectThe method encapsulated by this delegate takes two parameters: the first is a MemberInfo object and the second is an Object. 方法确定 MemberInfo 对象是否与 Object指定的条件相匹配。The method determines whether the MemberInfo object matches the criteria specified by the Object. 可以为 Object 分配类 FieldAttributesMethodAttributesMethodImplAttributes的任何一个字段的值。The Object may be assigned the value of any one of the fields on the classes FieldAttributes, MethodAttributes, or MethodImplAttributes.

例如,可以将 Object 中的字段的值分配 FieldAttributes 例如 Public。For example, the Object can be assigned the value of a field from FieldAttributes such as Public. 在这种情况下,当调用 FilterAttribute 委托时,仅当 MemberInfo 对象表示的方法使用元数据中的公共字段特性修饰时,它才会返回 trueIn that case, when the FilterAttribute delegate is invoked, it will return true only if the method represented by the MemberInfo object is decorated with the public field attribute in metadata.

适用于

另请参阅