auto_gcroot::operator bool

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Operator for using auto_gcroot in a conditional expression.

Syntax

operator bool() const;

Return Value

true if the wrapped object is valid; false otherwise.

Remarks

This operator actually converts to _detail_class::_safe_bool which is safer than bool because it cannot be converted to an integral type.

Example

// msl_auto_gcroot_operator_bool.cpp  
// compile with: /clr  
#include <msclr\auto_gcroot.h>  
  
using namespace System;  
using namespace msclr;  
  
int main() {  
   auto_gcroot<String^> s;  
   if ( s ) Console::WriteLine( "s is valid" );  
   if ( !s ) Console::WriteLine( "s is invalid" );  
   s = "something";  
   if ( s ) Console::WriteLine( "now s is valid" );  
   if ( !s ) Console::WriteLine( "now s is invalid" );  
   s.reset();  
   if ( s ) Console::WriteLine( "now s is valid" );  
   if ( !s ) Console::WriteLine( "now s is invalid" );  
}

s is invalid  
now s is valid  
now s is invalid

Requirements

Header file <msclr\auto_gcroot.h>

Namespace msclr

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