auto_gcroot::operator=

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Assignment operator.

Syntax

auto_gcroot<_element_type> & operator=(  
   _element_type _right  
);  
auto_gcroot<_element_type> & operator=(  
   auto_gcroot<_element_type> & _right  
);  
template<typename _other_type>  
auto_gcroot<_element_type> & operator=(  
   auto_gcroot<_other_type> & _right  
);

Parameters

_right
The object or auto_gcroot to be assigned to the current auto_gcroot.

Return Value

The current auto_gcroot, now owning _right.

Example

// msl_auto_gcroot_operator_equals.cpp  
// compile with: /clr  
#include <msclr\auto_gcroot.h>  
  
using namespace System;  
using namespace msclr;  
  
ref class ClassA {  
protected:  
   String^ m_s;     
public:  
   ClassA(String^ s) : m_s(s) {  
      Console::WriteLine( "in ClassA constructor: " + m_s );  
   }  
   ~ClassA() {  
      Console::WriteLine( "in ClassA destructor: " + m_s );  
   }  
  
   virtual void PrintHello() {  
      Console::WriteLine( "Hello from {0} A!", m_s );  
   }  
};  
  
ref class ClassB : ClassA {  
public:     
   ClassB( String^ s ) : ClassA( s ) {}  
   virtual void PrintHello() new {  
      Console::WriteLine( "Hello from {0} B!", m_s );  
   }  
};  
  
int main()  
{  
   auto_gcroot<ClassA^> a;  
   auto_gcroot<ClassA^> a2(gcnew ClassA( "first" ) );  
   a = a2; // assign from same type  
   a->PrintHello();  
  
   ClassA^ ha = gcnew ClassA( "second" );  
   a = ha; // assign from raw handle  
  
   auto_gcroot<ClassB^> b(gcnew ClassB( "third" ) );     
   b->PrintHello();  
   a = b; // assign from derived type     
   a->PrintHello();  
  
   Console::WriteLine("done");  
}

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

Requirements

Header file <msclr\auto_gcroot.h>

Namespace msclr

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