Type.IsByRef 属性
定义
重要
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获取一个值，该值指示 Type 是否由引用传递。
public:
virtual property bool IsByRef { bool get(); };public:
property bool IsByRef { bool get(); };public virtual bool IsByRef { get; }public bool IsByRef { get; }member this.IsByRef : boolPublic Overridable ReadOnly Property IsByRef As BooleanPublic ReadOnly Property IsByRef As Boolean属性值
如果 Type 按引用传递，则为 true；否则为 false。
实现
示例
下面的示例演示如何使用 属性检查是否通过引用 IsByRef 传递指定类型。 该示例定义类 MyTypeDelegator ，该类替代 HasElementTypeImpl 方法。 主类检查 属性 HasElementType 并显示元素类型。
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 );
}
}
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);
}
}
}
Imports System.Reflection
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
' 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
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
End Class
注解
若要获取实际类型，请取消引用通过引用传递的类型，然后对类型 GetElementType 调用 。