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.NET Framework Class Library
Type..::.IsByRef Property

Gets a value indicating whether the Type is passed by reference.

Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
Public ReadOnly Property IsByRef As Boolean
public bool IsByRef { get; }
public:
virtual property bool IsByRef {
	bool get () sealed;
}
abstract IsByRef : bool
override IsByRef : bool

Property Value

Type: System..::.Boolean
true if the Type is passed by reference; otherwise, false.

Implements

_Type..::.IsByRef
Remarks

To get to the actual type, dereference the type that was passed by reference, and then call GetElementType on that type.

Examples

The following example demonstrates a use of the IsByRef property to check whether a specified type is passed by reference. The example defines the class MyTypeDelegator, which overrides the HasElementTypeImpl method. The main class checks for the HasElementType property and displays the element type.


Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic
Public Class MyTypeDelegator
    Inherits TypeDelegator
    Public myElementType As String = Nothing
    Private myType As Type = Nothing
    Public Sub New(ByVal myType As Type)
        MyBase.New(myType)
        Me.myType = myType
    End Sub 'New
    ' Override Type.HasElementTypeImpl().
    Protected Overrides Function HasElementTypeImpl() As Boolean
        ' Determine whether the type is an array.
        If myType.IsArray Then
            myElementType = "array"
            Return True
        End If
        ' Determine whether the type is a reference.
        If myType.IsByRef Then
            myElementType = "reference"
            Return True
        End If
        ' Determine whether the type is a pointer.
        If myType.IsPointer Then
            myElementType = "pointer"
            Return True
        End If
        ' The type is not a reference, array, or pointer type.
        Return False
    End Function 'HasElementTypeImpl
End Class 'MyTypeDelegator
Public Class Type_HasElementTypeImpl
    Public Shared Sub Main()
        Try
            Dim myInt As Integer = 0
            Dim myArray(4) As Integer
            Dim myType As New MyTypeDelegator(myArray.GetType())
            Console.WriteLine(ControlChars.NewLine + "Determine whether a variable refers to an array or pointer or reference type." + ControlChars.NewLine)
            ' Determine whether myType is an array, pointer, reference type.  
            If myType.HasElementType Then
                Console.WriteLine("The type of myArray is {0}.", myType.myElementType.ToString())
            Else
                Console.WriteLine("myArray is not an array, pointer, or reference type.")
            End If
            myType = New MyTypeDelegator(myInt.GetType())
            ' Determine whether myType is an array, pointer, reference type. 
            If myType.HasElementType Then
                Console.WriteLine("The type of myInt is {0}.", myType.myElementType.ToString())
            Else
                Console.WriteLine("myInt is not an array, pointer, or reference type.")
            End If
        Catch e As Exception
            Console.WriteLine("Exception: {0}", e.Message.ToString())
        End Try
    End Sub 'Main
End Class 'Type_HasElementTypeImpl


using System;
using System.Reflection;
public class MyTypeDelegator : TypeDelegator
{
    public string myElementType = null;
    private Type myType = null ; 
    public MyTypeDelegator(Type myType) : base(myType)
    {
        this.myType = myType;
    }
    // Override Type.HasElementTypeImpl().
    protected override bool HasElementTypeImpl()
    {
        // Determine whether the type is an array.
        if(myType.IsArray)
        {
            myElementType = "array";
            return true;
        }
        // Determine whether the type is a reference.
        if(myType.IsByRef)
        {
            myElementType = "reference";
            return true;
        }
        // Determine whether the type is a pointer.
        if(myType.IsPointer)
        { 
            myElementType = "pointer";
            return true;
        }
        // Return false if the type is not a reference, array, or pointer type.
        return false;
    }  
}
public class Type_HasElementTypeImpl
{
    public static void Main()
    {
        try
        {
            int myInt = 0 ; 
            int[] myArray = new int[5];
            MyTypeDelegator myType = new MyTypeDelegator(myArray.GetType());
            // Determine whether myType is an array, pointer, reference type.  
            Console.WriteLine("\nDetermine whether a variable is an array, pointer, or reference type.\n");
            if( myType.HasElementType)
                Console.WriteLine("The type of myArray is {0}.", myType.myElementType);
            else
                Console.WriteLine("myArray is not an array, pointer, or reference type.");
            myType = new MyTypeDelegator(myInt.GetType());
            // Determine whether myType is an array, pointer, reference type. 
            if( myType.HasElementType)
                Console.WriteLine("The type of myInt is {0}.", myType.myElementType);
            else
                Console.WriteLine("myInt is not an array, pointer, or reference type.");
        }
        catch( Exception e )
        {
            Console.WriteLine("Exception: {0}", e.Message);
        }
    }
}


using namespace System;
using namespace System::Reflection;
public ref class MyTypeDelegator: public TypeDelegator
{
public:
   String^ myElementType;

private:
   Type^ myType;

public:
   MyTypeDelegator( Type^ myType )
      : TypeDelegator( myType )
   {
      this->myType = myType;
   }


protected:

   // Override Type::HasElementTypeImpl().
   virtual bool HasElementTypeImpl() override
   {

      // Determine whether the type is an array.
      if ( myType->IsArray )
      {
         myElementType = "array";
         return true;
      }


      // Determine whether the type is a reference.
      if ( myType->IsByRef )
      {
         myElementType = "reference";
         return true;
      }


      // Determine whether the type is a pointer.
      if ( myType->IsPointer )
      {
         myElementType = "pointer";
         return true;
      }


      // Return false if the type is not a reference, array, or pointer type.
      return false;
   }

};

int main()
{
   try
   {
      int myInt = 0;
      array<Int32>^myArray = gcnew array<Int32>(5);
      MyTypeDelegator^ myType = gcnew MyTypeDelegator( myArray->GetType() );

      // Determine whether myType is an array, pointer, reference type.
      Console::WriteLine( "\nDetermine whether a variable is an array, pointer, or reference type.\n" );
      if ( myType->HasElementType )
            Console::WriteLine( "The type of myArray is {0}.", myType->myElementType );
      else
            Console::WriteLine( "myArray is not an array, pointer, or reference type." );
      myType = gcnew MyTypeDelegator( myInt.GetType() );

      // Determine whether myType is an array, pointer, reference type.
      if ( myType->HasElementType )
            Console::WriteLine( "The type of myInt is {0}.", myType->myElementType );
      else
            Console::WriteLine( "myInt is not an array, pointer, or reference type." );
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( "Exception: {0}", e->Message );
   }

}


Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Portable Class Library

Supported in: Portable Class Library
Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.
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