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auto_handle::auto_handle

The auto_handle constructor.

auto_handle();
auto_handle(
   _element_type ^ _ptr
);
auto_handle(
   auto_handle<_element_type> % _right
);
template<typename _other_type>
auto_handle(
   auto_handle<_other_type> % _right
);

Parameters

  • _ptr
    The object to own.

  • _right
    An existing auto_handle.

Example

// msl_auto_handle_auto_handle.cpp
// compile with: /clr
#include "msclr\auto_handle.h"

using namespace System;
using namespace msclr;
ref class RefClassA {
protected:
   String^ m_s;   
public:
   RefClassA(String^ s) : m_s(s) {
      Console::WriteLine( "in RefClassA constructor: " + m_s );
   }
   ~RefClassA() {
      Console::WriteLine( "in RefClassA destructor: " + m_s );
   }

   virtual void PrintHello() {
      Console::WriteLine( "Hello from {0} A!", m_s );
   }
};

ref class RefClassB : RefClassA {
public:   
   RefClassB( String^ s ) : RefClassA( s ) {}
   virtual void PrintHello() new {
      Console::WriteLine( "Hello from {0} B!", m_s );
   }
};

int main()
{
   {
      auto_handle<RefClassA> a(gcnew RefClassA( "first" ) );
      a->PrintHello();
   }

   {
      auto_handle<RefClassB> b(gcnew RefClassB( "second" ) );
      b->PrintHello();
      auto_handle<RefClassA> a(b); //construct from derived type
      a->PrintHello();
      auto_handle<RefClassA> a2(a); //construct from same type
      a2->PrintHello();
   }

   Console::WriteLine("done");
}

in RefClassA constructor: first
Hello from first A!
in RefClassA destructor: first
in RefClassA constructor: second
Hello from second B!
Hello from second A!
Hello from second A!
in RefClassA destructor: second
done

Requirements

Header file <msclr\auto_handle.h>

Namespace msclr

See Also

Concepts

auto_handle Members

auto_handle::operator=

auto_handle::~auto_handle