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ParameterInfo.IsDefined(Type, Boolean) メソッド

定義

指定された型またはその派生型のカスタム属性がこのパラメーターに適用されているかどうかを判定します。

public:
 virtual bool IsDefined(Type ^ attributeType, bool inherit);
public virtual bool IsDefined (Type attributeType, bool inherit);
abstract member IsDefined : Type * bool -> bool
override this.IsDefined : Type * bool -> bool
Public Overridable Function IsDefined (attributeType As Type, inherit As Boolean) As Boolean

パラメーター

attributeType
Type

検索する Type オブジェクト。

inherit
Boolean

この型のオブジェクトでは、この引数は無視されます。

戻り値

このパラメーターに attributeType またはその派生型のインスタンスが 1 つ以上適用されている場合は true。それ以外の場合は false

実装

例外

attributeTypenullです。

attributeType が、共通言語ランライムで提供されている Type オブジェクトではありません。

次の例では、 MyAttributeMyDerivedAttributeの 2 つのカスタム属性を定義します。 MyDerivedAttribute は、MyAttribute から派生しています。 次に、これらの属性をサンプル クラスのメソッドのパラメーターに適用します。

この例を実行すると、 メソッドを IsDefined 使用して、サンプル クラス内のすべてのメソッドのすべてのパラメーターをテストします。 次に、 または MyDerivedAttributeを持つMyAttributeパラメーターが表示されます。

// System::Reflection::ParameterInfo::GetCustomAttributes(Type, bool)
// System::Reflection::ParameterInfo::IsDefined(Type, bool)
using namespace System;
using namespace System::Reflection;

// Define a custom attribute with one named parameter.
[AttributeUsage(AttributeTargets::Parameter)]
public ref class MyAttribute: public Attribute
{
private:
   String^ myName;

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

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

// Derive another custom attribute from MyAttribute.
[AttributeUsage(AttributeTargets::Parameter)]
public ref class MyDerivedAttribute: public MyAttribute
{
public:
   MyDerivedAttribute( String^ name ) : MyAttribute( name ) {}
};

// Define a class with a method that has three parameters. Apply
// MyAttribute to one parameter, MyDerivedAttribute to another, and
// no attributes to the third. 
public ref class MyClass1
{
public:
   void MyMethod( [MyAttribute("This is an example parameter attribute")] 
                  int i,
                  [MyDerivedAttribute("This is another parameter attribute")] 
                  int j,
                  int k ){}
};

void main()
{
   // Get the type of the class 'MyClass1'.
   Type^ myType = MyClass1::typeid;

   // Get the members associated with the class 'MyClass1'.
   array<MethodInfo^>^myMethods = myType->GetMethods();

   // For each method of the class 'MyClass1', display all the parameters
   // to which MyAttribute or its derived types have been applied.
   for each ( MethodInfo^ mi in myMethods )
   {
      // Get the parameters for the method.
      array<ParameterInfo^>^ myParameters = mi->GetParameters();
      if ( myParameters->Length > 0 )
      {
         Console::WriteLine("\nThe following parameters of {0} have MyAttribute or a derived type:", mi);
         for each ( ParameterInfo^ pi in myParameters)
         {
            if (pi->IsDefined(MyAttribute::typeid, false))
            {
               Console::WriteLine("Parameter {0}, name = {1}, type = {2}", 
                  pi->Position, pi->Name, pi->ParameterType);
            }
         }
      }
   }
}

/* This code example produces the following output:

The following parameters of Void MyMethod(Int32, Int32, Int32) have MyAttribute or a derived type:
Parameter 0, name = i, type = System.Int32
Parameter 1, name = j, type = System.Int32

The following parameters of Boolean Equals(System.Object) have MyAttribute or a derived type:
 */
using System;
using System.Reflection;

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

// Derive another custom attribute from MyAttribute
[AttributeUsage(AttributeTargets.Parameter)]
public class MyDerivedAttribute : MyAttribute
{
    public MyDerivedAttribute(string name) : base(name) {}
}

// Define a class with a method that has three parameters. Apply
// MyAttribute to one parameter, MyDerivedAttribute to another, and
// no attributes to the third.
public class MyClass1
{
    public void MyMethod(
        [MyAttribute("This is an example parameter attribute")]
        int i,
        [MyDerivedAttribute("This is another parameter attribute")]
        int j,
        int k )
    {
        return;
    }
}

public class MemberInfo_GetCustomAttributes
{
    public static void Main()
    {
        // Get the type of the class 'MyClass1'.
        Type myType = typeof(MyClass1);
        // Get the members associated with the class 'MyClass1'.
        MethodInfo[] myMethods = myType.GetMethods();

        // For each method of the class 'MyClass1', display all the parameters
        // to which MyAttribute or its derived types have been applied.
        foreach (MethodInfo mi in myMethods)
        {
            // Get the parameters for the method.
            ParameterInfo[] myParameters = mi.GetParameters();
            if (myParameters.Length > 0)
            {
                Console.WriteLine("\nThe following parameters of {0} have MyAttribute or a derived type: ", mi);
                foreach (ParameterInfo pi in myParameters)
                {
                    if (pi.IsDefined(typeof(MyAttribute), false))
                    {
                        Console.WriteLine("Parameter {0}, name = {1}, type = {2}",
                            pi.Position, pi.Name, pi.ParameterType);
                    }
                }
            }
        }
    }
}

/* This code example produces the following output:

The following parameters of Void MyMethod(Int32, Int32, Int32) have MyAttribute or a derived type:
Parameter 0, name = i, type = System.Int32
Parameter 1, name = j, type = System.Int32

The following parameters of Boolean Equals(System.Object) have MyAttribute or a derived type:
 */
Imports System.Reflection

' Define a custom attribute with one named parameter.
<AttributeUsage(AttributeTargets.Parameter)> _
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 

' Derive another custom attribute from MyAttribute
<AttributeUsage(AttributeTargets.Parameter)> _
Public Class MyDerivedAttribute
    Inherits MyAttribute

    Public Sub New(ByVal name As String)
        MyBase.New(name)
    End Sub 
End Class

' Define a class with a method that has three parameters. Apply
' MyAttribute to one parameter, MyDerivedAttribute to another, and
' no attributes to the third. 
Public Class MyClass1

    Public Sub MyMethod(<MyAttribute("This is an example parameter attribute")> _
                        ByVal i As Integer, _
                        <MyDerivedAttribute("This is another parameter attribute")> _
                        ByVal j As Integer, _
                        ByVal k As Integer)
        Return
    End Sub 
End Class 

Public Class MemberInfo_GetCustomAttributes

    Public Shared Sub Main()
        ' Get the type of the class 'MyClass1'.
        Dim myType As Type = GetType(MyClass1)
        ' Get the members associated with the class 'MyClass1'.
        Dim myMethods As MethodInfo() = myType.GetMethods()

        ' For each method of the class 'MyClass1', display all the parameters
        ' to which MyAttribute or its derived types have been applied.
        For Each mi As MethodInfo In myMethods
            ' Get the parameters for the method.
            Dim myParameters As ParameterInfo() = mi.GetParameters()
            If myParameters.Length > 0 Then
                Console.WriteLine(vbCrLf & "The following parameters of {0} have MyAttribute or a derived type: ", mi)
                For Each pi As ParameterInfo In myParameters
                    If pi.IsDefined(GetType(MyAttribute), False) Then
                        Console.WriteLine("Parameter {0}, name = {1}, type = {2}", _
                            pi.Position, pi.Name, pi.ParameterType)
                    End If
                Next
            End If
        Next
    End Sub 
End Class 

' This code example produces the following output:
'
'The following parameters of Void MyMethod(Int32, Int32, Int32) have MyAttribute or a derived type:
'Parameter 0, name = i, type = System.Int32
'Parameter 1, name = j, type = System.Int32
'
'The following parameters of Boolean Equals(System.Object) have MyAttribute or a derived type:

注釈

このメソッドは パラメーターを inherit 無視します。 継承チェーンでパラメーターの属性を検索するには、 メソッドの適切なオーバーロードを Attribute.IsDefined 使用します。

適用対象