次の方法で共有

FieldInfo.IsStatic プロパティ

フィールドが静的かどうかを示す値を取得します。

Public ReadOnly Property IsStatic As Boolean
[C#]
public bool IsStatic {get;}
[C++]
public: __property bool get_IsStatic();
[JScript]
public function get IsStatic() : Boolean;

プロパティ値

フィールドが静的な場合は true 。それ以外の場合は false 。

解説

フィールドが静的な場合は、フィールドの 1 つのコピーが型のすべてのインスタンスで共有されます。

IsStatic プロパティは、 FieldAttributes.Static 属性が設定されたときに設定されます。

IsStatic プロパティを取得するには、最初に Type クラスを取得します。そして、その Type から FieldInfo を取得します。最後に、 FieldInfo から IsStatic プロパティを取得します。非パブリック フィールドにアクセスするには、 GetField メソッドで BindingFlags を NonPublic に設定し、アクセシビリティを Instance または Static に設定します。

使用例

指定したフィールドが静的かどうかを調べ、その結果を表示する例を次に示します。

 
Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic

' Make two fields.
Public Class Myfielda
    Private m_field As String = "A private field"

    Public Property Field() As String
        Get
            Return m_field
        End Get
        Set(ByVal Value As String)
            If m_field <> value Then
                m_field = value
            End If
        End Set
    End Property
End Class

Public Class Myfieldb
    Private Shared m_field As String = "B static field"

    Public Property Field() As String
        Get
            Return m_field
        End Get
        Set(ByVal Value As String)
            If m_field <> value Then
                m_field = value
            End If
        End Set
    End Property
End Class

Public Class Myfieldinfo

    Public Shared Sub Main()
        Console.WriteLine()
        Console.WriteLine("Reflection.FieldInfo")
        Console.WriteLine()
        Dim Myfielda As New Myfielda()
        Dim Myfieldb As New Myfieldb()

        ' Get the Type and FieldInfo.
        Dim MyTypea As Type = Type.GetType("Myfielda")
        Dim Myfieldinfoa As FieldInfo = _
           MyTypea.GetField("m_field", BindingFlags.NonPublic Or BindingFlags.Instance)
        Dim MyTypeb As Type = Type.GetType("Myfieldb")
        Dim Myfieldinfob As FieldInfo = _
           MyTypeb.GetField("m_field", BindingFlags.NonPublic Or BindingFlags.Static)

        ' For the first field, get and display the name, field, and IsStatic property value.
        Console.WriteLine("{0} - {1}; IsStatic - {2}", MyTypea.FullName, Myfieldinfoa.GetValue(Myfielda), Myfieldinfoa.IsStatic)

        ' For the second field, get and display the name, field, and IsStatic property value.
        Console.WriteLine("{0} - {1}; IsStatic - {2}", MyTypeb.FullName, Myfieldinfob.GetValue(Myfieldb), Myfieldinfob.IsStatic)

    End Sub
End Class

[C#] 
using System;
using System.Reflection;

 // Make two fields.
public class Myfielda
{
    private string field = "A private field";
    public string Field
    {
        get{return field;}
        set{if(field!=value){field=value;}}
    }
}
public class Myfieldb
{
    static string field = "B static field";
    public string Field 
    {
        get{return field;}
        set{if(field!=value){field=value;}}
    }
}
  
public class Myfieldinfo
{
    public static int Main()
    {
        Console.WriteLine("\nReflection.FieldInfo");
        Myfielda Myfielda = new Myfielda();
        Myfieldb Myfieldb = new Myfieldb();
  
        // Get the Type and FieldInfo.
        Type MyTypea = Type.GetType("Myfielda");
        FieldInfo Myfieldinfoa = MyTypea.GetField("field", BindingFlags.NonPublic|BindingFlags.Instance);
        Type MyTypeb = Type.GetType("Myfieldb");
        FieldInfo Myfieldinfob = MyTypeb.GetField("field", BindingFlags.NonPublic|BindingFlags.Static);
  
        // For the first field, get and display the name, field, and IsStatic property value.
        Console.Write("\n{0} - ", MyTypea.FullName);
        Console.Write("{0}; ", Myfieldinfoa.GetValue(Myfielda));
        Console.Write("IsStatic - {0}", Myfieldinfoa.IsStatic);
  
        // For the second field get and display the name, field, and IsStatic property value.
        Console.Write("\n{0} - ", MyTypeb.FullName);
        Console.Write("{0}; ", Myfieldinfob.GetValue(Myfieldb));
        Console.Write("IsStatic - {0}", Myfieldinfob.IsStatic);
  
        return 0;
    }
}

[C++] 
#using <mscorlib.dll>
using namespace System;
using namespace System::Reflection;

// Make two fields.
public __gc class Myfielda
{
private:
    String* field;
public:
    Myfielda() : field(S"A private field") {}
    __property String* get_Field() {
        return field;
    }
    __property void set_Field(String* value) {
        if(field!=value){
            field=value;
        }
    }
};
public __gc class Myfieldb
{
    static String* field = S"B static field";
public:
    __property String* get_Field() {
        return field;
    }
    __property void set_Field(String* value) {
        if(field!=value){
            field=value;
        }
    }
};

int main()
{
    Console::WriteLine(S"\nReflection.FieldInfo");
    Myfielda* myfielda = new Myfielda();
    Myfieldb* myfieldb = new Myfieldb();

    // Get the Type and FieldInfo.
    Type* MyTypea = Type::GetType(S"Myfielda");
    FieldInfo* Myfieldinfoa = MyTypea->GetField(S"field",
        static_cast<BindingFlags>(BindingFlags::NonPublic|BindingFlags::Instance));
    Type* MyTypeb = Type::GetType(S"Myfieldb");
    FieldInfo* Myfieldinfob = MyTypeb->GetField(S"field",
        static_cast<BindingFlags>(BindingFlags::NonPublic|BindingFlags::Static));

    // For the first field, get and display the name, field, and IsStatic property value.
    Console::Write(S"\n{0} - ", MyTypea->FullName);
    Console::Write(S"{0}; ", Myfieldinfoa->GetValue(myfielda));
    Console::Write(S"IsStatic - {0}", __box(Myfieldinfoa->IsStatic));

    // For the second field get and display the name, field, and IsStatic property value.
    Console::Write(S"\n{0} - ", MyTypeb->FullName);
    Console::Write(S"{0}; ", Myfieldinfob->GetValue(myfieldb));
    Console::Write(S"IsStatic - {0}", __box(Myfieldinfob->IsStatic));

    return 0;
}

[JScript] 
//Make two fields.
public class Myfielda
{
   private var field : String = "A private field";
   public function get Field() : String {
       return field;
   }
   
   public function set Field(value : String) {
       if(field!=value)field=value;
   }
}
public class Myfieldb
{
   private static var field : String = "B static field";
   public static function get Field() : String  {
       return field;
   }
   public static function set Field(value : String) {
       if(field!=value) field=value;
   }
}
 
public class Myfieldinfo
{
   public static function Main() : void
   {
      Console.WriteLine("\nReflection.FieldInfo");
      var myfielda : Myfielda = new Myfielda();
      var myfieldb : Myfieldb = new Myfieldb();
 
      //Get the Type and FieldInfo.
      var MyTypea : Type = Type.GetType("Myfielda");
      var Myfieldinfoa : FieldInfo = MyTypea.GetField("field", BindingFlags.NonPublic|BindingFlags.Instance);
      var MyTypeb : Type = Type.GetType("Myfieldb");
      var Myfieldinfob : FieldInfo = MyTypeb.GetField("field", BindingFlags.NonPublic|BindingFlags.Static);
 
      //For the first field, get and display the name, field, and IsStatic.
      Console.Write("\n{0} - ", MyTypea.FullName);
      Console.Write("{0}; ", Myfieldinfoa.GetValue(myfielda));
      Console.Write("IsStatic - {0}", Myfieldinfoa.IsStatic);
 
      //For the second field get and display the name, field, and IsStatic.
      Console.Write("\n{0} - ", MyTypeb.FullName);
      Console.Write("{0}; ", Myfieldinfob.GetValue(myfieldb));
      Console.Write("IsStatic - {0}", Myfieldinfob.IsStatic);
   }
}
Myfieldinfo.Main();

このコードによって、次の出力が生成されます。

Reflection.FieldInfo

Myfielda - A private field; IsStatic - False

Myfieldb - B static field; IsStatic - True

必要条件

プラットフォーム: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 ファミリ, .NET Compact Framework - Windows CE .NET

参照

FieldInfo クラス | FieldInfo メンバ | System.Reflection 名前空間 | FieldAttributes | GetField | Type

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