MemberInfo.GetCustomAttributes 方法

參考

定義

命名空間:: System.Reflection

組件:: System.Runtime.dll

組件:: mscorlib.dll

組件:: netstandard.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

在衍生類別中覆寫時，傳回套用至此成員的自訂屬性。

多載

GetCustomAttributes(Boolean)	在衍生類別中覆寫時，傳回套用至此成員之所有自訂屬性的陣列。
GetCustomAttributes(Type, Boolean)	當在衍生的類別中覆寫時，會傳回套用至這個成員的自訂屬性陣列，並以 Type 識別。

GetCustomAttributes(Boolean)

來源:: MemberInfo.cs

來源:: MemberInfo.cs

來源:: MemberInfo.cs

在衍生類別中覆寫時，傳回套用至此成員之所有自訂屬性的陣列。

public:
 abstract cli::array <System::Object ^> ^ GetCustomAttributes(bool inherit);

public abstract object[] GetCustomAttributes (bool inherit);

abstract member GetCustomAttributes : bool -> obj[]

Public MustOverride Function GetCustomAttributes (inherit As Boolean) As Object()

參數

inherit: Boolean

true 表示要搜尋這個成員的繼承鏈結以尋找屬性；否則為 false。這個參數會忽略屬性和事件。

傳回

Object[]

包含套用至此成員之所有自訂屬性的陣列，如果沒有定義屬性，則為包含零個元素的陣列。

實作

GetCustomAttributes(Boolean) GetCustomAttributes(Boolean)

例外狀況

InvalidOperationException

這個成員所屬的型別已載入僅限反映的內容中。請參閱如何：將組件載入僅限反映的內容。

TypeLoadException

無法載入自訂屬性型別。

範例

下列範例會定義自定義屬性，並將屬性與 MyClass.MyMethod產生關聯，並在運行時間擷取屬性，並顯示結果。

using namespace System;
using namespace System::Reflection;

// Define a custom attribute with one named parameter.

[AttributeUsage(AttributeTargets::All)]
public ref class MyAttribute: public Attribute
{
private:
   String^ myName;

public:
   MyAttribute( String^ name )
   {
      myName = name;
   }

   property String^ Name 
   {
      String^ get()
      {
         return myName;
      }
   }
};

// Define a class that has the custom attribute associated with one of its members.
public ref class MyClass1
{
public:

   [MyAttribute("This is an example attribute.")]
   void MyMethod( int i )
   {
      return;
   }
};

int main()
{
   try
   {
      // Get the type of MyClass1.
      Type^ myType = MyClass1::typeid;

      // Get the members associated with MyClass1.
      array<MemberInfo^>^myMembers = myType->GetMembers();

      // Display the attributes for each of the members of MyClass1.
      for ( int i = 0; i < myMembers->Length; i++ )
      {
         array<Object^>^myAttributes = myMembers[ i ]->GetCustomAttributes( true );
         if ( myAttributes->Length > 0 )
         {
            Console::WriteLine( "\nThe attributes for the member {0} are: \n", myMembers[ i ] );
            for ( int j = 0; j < myAttributes->Length; j++ )
               Console::WriteLine( "The type of the attribute is {0}.", myAttributes[ j ] );
         }
      }
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "An exception occurred: {0}", e->Message );
   }
}

using System;
using System.Reflection;

// Define a custom attribute with one named parameter.
[AttributeUsage(AttributeTargets.All)]
public class MyAttribute : Attribute
{
    private string myName;
    public MyAttribute(string name)
    {
        myName = name;
    }
    public string Name
    {
        get
        {
            return myName;
        }
    }
}

// Define a class that has the custom attribute associated with one of its members.
public class MyClass1
{
    [MyAttribute("This is an example attribute.")]
    public void MyMethod(int i)
    {
        return;
    }
}

public class MemberInfo_GetCustomAttributes
{
    public static void Main()
    {
        try
        {
            // Get the type of MyClass1.
            Type myType = typeof(MyClass1);
            // Get the members associated with MyClass1.
            MemberInfo[] myMembers = myType.GetMembers();

            // Display the attributes for each of the members of MyClass1.
            for(int i = 0; i < myMembers.Length; i++)
            {
                Object[] myAttributes = myMembers[i].GetCustomAttributes(true);
                if(myAttributes.Length > 0)
                {
                    Console.WriteLine("\nThe attributes for the member {0} are: \n", myMembers[i]);
                    for(int j = 0; j < myAttributes.Length; j++)
                        Console.WriteLine("The type of the attribute is {0}.", myAttributes[j]);
                }
            }
        }
        catch(Exception e)
        {
            Console.WriteLine("An exception occurred: {0}", e.Message);
        }
    }
}

Imports System.Reflection

' Define a custom attribute with one named parameter.
<AttributeUsage(AttributeTargets.All)> Public Class MyAttribute
    Inherits Attribute
    Private myName As String

    Public Sub New(ByVal name As String)
        myName = name
    End Sub

    Public ReadOnly Property Name() As String
        Get
            Return myName
        End Get
    End Property
End Class

' Define a class that has the custom attribute associated with one of its members.
Public Class MyClass1

    <MyAttribute("This is an example attribute.")> Public Sub MyMethod(ByVal i As Integer)
        Return
    End Sub
End Class


Public Class MemberInfo_GetCustomAttributes

    Public Shared Sub Main()
        Try
            ' Get the type of MyClass1.
            Dim myType As Type = GetType(MyClass1)
            ' Get the members associated with MyClass1.
            Dim myMembers As MemberInfo() = myType.GetMembers()

            ' Display the attributes for each of the members of MyClass1.
            Dim i As Integer
            For i = 0 To myMembers.Length - 1
                Dim myAttributes As [Object]() = myMembers(i).GetCustomAttributes(False)
                If myAttributes.Length > 0 Then
                    Console.WriteLine("The attributes for the member {0} are: ", myMembers(i))
                    Dim j As Integer
                    For j = 0 To myAttributes.Length - 1
                        Console.WriteLine("The type of the attribute is: {0}", myAttributes(j))
                    Next j
                End If
            Next i
        Catch e As Exception
            Console.WriteLine("An exception occurred: {0}.", e.Message)
        End Try
    End Sub
End Class

備註

這個方法會 inherit 忽略屬性和事件的參數。若要搜尋屬性和事件的屬性繼承鏈結，請使用方法的適當 Attribute.GetCustomAttributes 多載。

注意

在 .NET Framework 2.0 版中，如果方法是以新的元數據格式儲存，則此方法會傳回方法、建構函式和類型的安全性屬性。使用 2.0 版編譯的元件會使用此格式。使用舊版 .NET Framework 編譯的動態元件和元件會使用舊的 XML 格式。請參閱發出宣告式安全性屬性。

另請參閱

適用於

GetCustomAttributes(Type, Boolean)

來源:: MemberInfo.cs

來源:: MemberInfo.cs

來源:: MemberInfo.cs

當在衍生的類別中覆寫時，會傳回套用至這個成員的自訂屬性陣列，並以 Type 識別。

public:
 abstract cli::array <System::Object ^> ^ GetCustomAttributes(Type ^ attributeType, bool inherit);

public abstract object[] GetCustomAttributes (Type attributeType, bool inherit);

abstract member GetCustomAttributes : Type * bool -> obj[]

Public MustOverride Function GetCustomAttributes (attributeType As Type, inherit As Boolean) As Object()

參數

attributeType: Type

要搜尋的屬性類型。只會傳回可指派給這種類型的屬性。

inherit: Boolean

true 表示要搜尋這個成員的繼承鏈結以尋找屬性；否則為 false。這個參數會忽略屬性和事件。

傳回

Object[]

套用至這個成員的自訂屬性陣列，或如果 attributeType 沒有套用任何可指派的屬性，則為零個項目的陣列。

實作

GetCustomAttributes(Type, Boolean) GetCustomAttributes(Type, Boolean)

例外狀況

TypeLoadException

無法載入自訂屬性型別。

ArgumentNullException

如果 attributeType 為 null。

InvalidOperationException

這個成員所屬的型別已載入僅限反映的內容中。請參閱如何：將組件載入僅限反映的內容。

範例

下列範例會定義名為 BaseClass 且具有兩個非繼承成員的類別：名為 total 的線程靜態欄位，以及名為 MethodA的非CLS相容方法。名為 DerivedClass 的類別繼承自 BaseClass ，並覆寫其 MethodA 方法。請注意，不會將任何屬性套用至的成員 DerivedClass。此範例會逐一查看的成員DerivedClass，以判斷或 ThreadStaticAttribute 屬性是否CLSCompliantAttribute套用至它們。因為 inherit 是 true，所以方法會搜尋的繼承階層 DerivedClass 中是否有指定的屬性。如範例的輸出所示， total 字段會以 ThreadStaticAttribute 屬性裝飾，而 MethodA 方法會以 CLSCompliantAttribute 屬性裝飾。

using System;

public class BaseClass
{
   [ThreadStatic] public int total;

   [CLSCompliant(false)] public virtual uint MethodA()
   {
      return (uint) 100;
   }
}

public class DerivedClass : BaseClass
{
   public override uint MethodA()
   {
      total++;
      return 200;
   }
}

public class Example
{
   public static void Main()
   {
      Type t = typeof(DerivedClass);
      Console.WriteLine("Members of {0}:", t.FullName);
      foreach (var m in t.GetMembers())
      {
         bool hasAttribute = false;
         Console.Write("   {0}: ", m.Name);
         if (m.GetCustomAttributes(typeof(CLSCompliantAttribute), true).Length > 0) {
            Console.Write("CLSCompliant");
            hasAttribute = true;
         }
         if (m.GetCustomAttributes(typeof(ThreadStaticAttribute), true).Length > 0) {
            Console.Write("ThreadStatic");
            hasAttribute = true;
         }
         if (! hasAttribute)
            Console.Write("No attributes");

         Console.WriteLine();
      }
   }
}
// The example displays the following output:
//       Members of DerivedClass:
//          MethodA: CLSCompliant
//          ToString: No attributes
//          Equals: No attributes
//          GetHashCode: No attributes
//          typeof: No attributes
//          .ctor: No attributes
//          total: ThreadStatic

Public Class BaseClass
   <ThreadStatic> Public total As Integer
   
   <CLSCompliant(False)> Public Overridable Function MethodA() As UInt32
      Return CUInt(100)
   End Function
End Class

Public Class DerivedClass : Inherits BaseClass
   Public Overrides Function MethodA() As UInt32
      total += 1
      Return 200
   End Function
End Class

Module Example
   Public Sub Main()
      Dim t As Type = GetType(DerivedClass)
      Console.WriteLine("Members of {0}:", t.FullName)
      For Each m In t.GetMembers()
         Dim hasAttribute As Boolean = False
         Console.Write("   {0}: ", m.Name)
         If m.GetCustomAttributes(GetType(CLSCompliantAttribute), True).Length > 0 Then
            Console.Write("CLSCompliant")
            hasAttribute = True
         End If
         If m.GetCustomAttributes(GetType(ThreadStaticAttribute), True).Length > 0 Then
            Console.Write("ThreadStatic")
            hasAttribute = True
         End If
         If Not hasAttribute Then
            Console.Write("No attributes")
         End If
         Console.WriteLine()
      Next
   End Sub
End Module
' The example displays the following output:
'       Members of DerivedClass:
'          MethodA: CLSCompliant
'          ToString: No attributes
'          Equals: No attributes
'          GetHashCode: No attributes
'          GetType: No attributes
'          .ctor: No attributes
'          total: ThreadStatic

備註

這個方法會 inherit 忽略屬性和事件的參數。若要搜尋屬性和事件的屬性繼承鏈結，請使用方法的適當 Attribute.GetCustomAttributes 多載。

注意

在 .NET Framework 2.0 版中，如果屬性以新的元數據格式儲存，這個方法會在方法、建構函式和類型上傳回安全性屬性。使用 2.0 版編譯的元件會使用此格式。使用舊版 .NET Framework 編譯的動態元件和元件會使用舊的 XML 格式。請參閱發出宣告式安全性屬性。

適用於

共用方式為

MemberInfo.GetCustomAttributes 方法

定義

多載

GetCustomAttributes(Boolean)

參數

傳回

實作

例外狀況

範例

備註

另請參閱

適用於

GetCustomAttributes(Type, Boolean)

參數

傳回

實作

例外狀況

範例

備註

適用於

其他資源