Gets a reference to the default binder, which implements internal rules for selecting the appropriate members to be called by InvokeMember.
Assembly: mscorlib (in mscorlib.dll)
Public Shared ReadOnly Property DefaultBinder As Binderpublic static Binder DefaultBinder { get; }public:
static property Binder^ DefaultBinder {
Binder^ get ();
}static member DefaultBinder : Binder
Property Value
Type: System.ReflectionA reference to the default binder used by the system.
The default binder provided with the common language runtime is applicable in all but the most specialized circumstances. If you need a binder that follows rules that differ from those of the supplied default binder, define a type derived from the Binder class and pass an instance of that type using the binder parameter of one of the InvokeMember overloads.
Reflection models the accessibility rules of the common type system. For example, if the caller is in the same assembly, the caller does not need special permissions for internal members. Otherwise, the caller needs ReflectionPermission. This is consistent with lookup of members that are protected, private, and so on.
The general principle is that ChangeType should perform only widening conversions, which never lose data. An example of a widening conversion is converting a value that is a 32-bit signed integer to a value that is a 64-bit signed integer. This is distinguished from a narrowing conversion, which may lose data. An example of a narrowing conversion is converting a 64-bit signed integer to a 32-bit signed integer.
The following table lists the conversions supported by the default binder.
Source Type | Target Type |
|---|---|
Any type | Its base type. |
Any type | The interface it implements. |
Char | Unt16, UInt32, Int32, UInt64, Int64, Single, Double |
Byte | Char, Unt16, Int16, UInt32, Int32, UInt64, Int64, Single, Double |
SByte | Int16, Int32, Int64, Single, Double |
UInt16 | UInt32, Int32, UInt64, Int64, Single, Double |
Int16 | Int32, Int64, Single, Double |
UInt32 | UInt64, Int64, Single, Double |
Int32 | Int64, Single, Double |
UInt64 | Single, Double |
Int64 | Single, Double |
Single | Double |
Non-reference | By-reference. |
The following example gets the default binder from the DefaultBinder property, and invokes a member of MyClass by passing the DefaultBinder value as a parameter to InvokeMember.
Imports System
Imports System.Reflection
Imports Microsoft.VisualBasic
Public Class MyDefaultBinderSample
Public Shared Sub Main()
Try
Dim defaultBinder As Binder = Type.DefaultBinder
Dim [myClass] As New [MyClass]()
' Invoke the HelloWorld method of MyClass.
[myClass].GetType().InvokeMember("HelloWorld", BindingFlags.InvokeMethod, defaultBinder, [myClass], New Object() {})
Catch e As Exception
Console.WriteLine("Exception :" + e.Message.ToString())
End Try
End Sub 'Main
Class [MyClass]
Public Sub HelloWorld()
Console.WriteLine("Hello World")
End Sub 'HelloWorld
End Class '[MyClass]
End Class 'MyDefaultBinderSample
using System;
using System.Reflection;
public class MyDefaultBinderSample
{
public static void Main()
{
try
{
Binder defaultBinder = Type.DefaultBinder;
MyClass myClass = new MyClass();
// Invoke the HelloWorld method of MyClass.
myClass.GetType().InvokeMember("HelloWorld", BindingFlags.InvokeMethod,
defaultBinder, myClass, new object [] {});
}
catch(Exception e)
{
Console.WriteLine("Exception :" + e.Message);
}
}
class MyClass
{
public void HelloWorld()
{
Console.WriteLine("Hello World");
}
}
}
using namespace System;
using namespace System::Reflection;
ref class MyClass
{
public:
void HelloWorld()
{
Console::WriteLine( "Hello World" );
}
};
int main()
{
try
{
Binder^ defaultBinder = Type::DefaultBinder;
MyClass^ myClass = gcnew MyClass;
// Invoke the HelloWorld method of MyClass.
myClass->GetType()->InvokeMember( "HelloWorld", BindingFlags::InvokeMethod, defaultBinder, myClass, nullptr );
}
catch ( Exception^ e )
{
Console::WriteLine( "Exception : {0}", e->Message );
}
}
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.