Discussion :

[lui88]

Bonjour ,

j'ai un probleme avec using namespace std; que j'utilise dans mon programme
j'utilise pourtant souvent using namespace std mais là je ne sais pas du tout ,j'ai aussi regardé dans la FAQ mais aucun resultat.merci de votre aide.

le compilateur me dit:
Erreur C2653: 'std'*: n'est pas un nom de classe ni d'espace de noms

Erreur C2676: '<<'*binaire : 'ostream' ne définit pas cet opérateur ou une conversion vers un type acceptable pour l'opérateur prédéfini

Erreur C2065: 'cout'*: identificateur non déclaré

Erreur C2065: 'endl'*: identificateur non déclaré

.h

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// Person-3.h
// Person class definition
 
#ifndef __Person_3_h__
#define __Person_3_h__
 
// class dependencies
 
using namespace std;
 
class ostream;
 
 
class Person
{
 // Attributes
 public:
	const char* get_first_name() const;
		// returns this person first name.
 
	void set_first_name(const char* new_first_name);
		// changes this person first name.
 
	const char* get_last_name() const;
		// returns this person last name.
 
	void set_last_name(const char* new_last_name);
		// changes this person last name.
 
	int get_age() const;
		// returns this person age.
 
	void set_age(int new_age);
		// changes this person age.
 
 // Operations
 public:
	 virtual void print(std::ostream& out) const;
		// dumps object properties to specified output stream.
 
 // Implementation
 public:
	Person();
		// constructs a not initialized (then invalid) person.
 
	Person(const Person& source_person);
		// constructs a person by duplicating an another one.
 
	Person(const char* first_name, const char* last_name, int age);
		// constructs a valid person.
 
	virtual ~Person();
		// frees this person and its allocated resources.
 
	Person& operator=(const Person& source_person);
		// overrides = operator for copy purpose.
 
 protected:
	char* _first_name;
		// this person first name (dynamic string).
 
	char* _last_name;
		// this person last name (dynamic string).
 
	int _age;
		// this person age.
};
 
 
// Inline functions implementation
 
 
inline const char* Person::get_first_name() const
{
	// returns person first name attribute
 
	cout << this << ".Person::get_first_name(); called" << endl;
 
 
	return _first_name;
}
 
 
inline const char* Person::get_last_name() const
{
	// returns person last name attribute
 
	cout << this << ".Person::get_last_name(); called" << endl;
 
 
	return _last_name;
}
 
 
inline int Person::get_age() const
{
	// returns person age attribute
 
	cout << this << ".Person::get_age(); called" << endl;
 
 
	return _age;
}
 
 
inline void Person::set_age(int new_age)
{
	// sets person age attribute
 
	cout << this << ".Person::set_age(new_age = \"" 
		<< new_age << "\"); called" << endl;
 
 
	_age = new_age;
}
 
#endif // __Person_3_h__

.Cpp

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// Person class implementation
 
#include <stdlib.h>
#include <iostream>
#include <stdafx.h>
#include <String.h>
 
#include "Person-3.h"
 
 
 
 
void Person::set_first_name(const char* new_first_name)
{
	// sets person first name attribute
 
	cout << this << ".Person::set_first_name(new_first_name = \"" 
		<< new_first_name << "\"); called" << endl;
 
 
	// delete previous first name if any
	if (_first_name != NULL)
		delete [] _first_name;
 
	// make an internal copy of passed string
	_first_name = new char [strlen(new_first_name) + 1];
	strcpy(_first_name, new_first_name);
}
 
 
void Person::set_last_name(const char* new_last_name)
{
	// sets person last name attribute
 
	cout << this << ".Person::set_last_name(new_last_name = \"" 
		<< new_last_name << "\"); called" << endl;
 
 
 
	// delete previous last name if any
	if (_last_name != NULL)
		delete [] _last_name;
 
	// make an internal copy of passed string
	_last_name = new char [strlen(new_last_name) + 1];
	strcpy(_last_name, new_last_name);
}
 
 
void Person::print(std::ostream& out) const
{
	// outputs person attributes
 
	cout << this << ".Person::print(out = " << &out << "); called" << endl;
 
 
	// output person info on specified output console
	out << _first_name << " " << _last_name << ", ";
	out << _age << " ans." << endl;
}
 
 
Person::Person()
{
	// constructs a not yet valid person
 
	cout << "Person::Person() called to construct " << this << endl;
 
 
	// set person initial state
	_first_name = NULL;
	_last_name = NULL;
	_age = -1;
}
 
 
Person::Person(const Person& source_person)
{
	// constructs a valid person by cloning
 
	cout << "Person::Person(source_person = " 
		<< &source_person << ") called to construct " << this << endl;
 
 
	// set person initial state
	_first_name = NULL;
	_last_name = NULL;
	_age = -1;
 
	// create person by cloning the specified one
	operator=(source_person);
}
 
 
Person::Person(const char* first_name, const char* last_name,
			   int age)
{
	// constructs a valid person from parameters
 
	cout << "Person::Person(first_name = \"" << first_name
		<< "\", last_name = \"" << last_name << "\", age = " << age 
		<< ") called to construct " << this << endl;
 
 
	// create person from passed parameters
	_first_name = NULL;
	set_first_name(first_name);
 
	_last_name = NULL;
	set_last_name(last_name);
 
	_age = age;
}
 
 
Person::~Person()
{
	// destructs this person
 
	cout << "Person::~Person() called to destruct " << this << endl;
 
 
	// free allocated resources
	if (_first_name != NULL)
		delete [] _first_name;
 
	if (_last_name != NULL)
		delete [] _last_name;
}
 
 
Person& Person::operator=(const Person& source_person)
{
	// sets person attributes by cloning
 
	cout << this << ".Person::operator=(source_person = "
		<< &source_person << ") called" << endl;
 
 
	// set this person attributes by cloning the passed person
	set_first_name(source_person._first_name);
	set_last_name(source_person._last_name);
	_age = source_person._age;
 
	return *this;
}

[3DArchi]

Bonjour,
D'abord, l'utilisation de using namespace std dans un en-tête est à bannir.
Ensuite, l'erreur est tout simplement liée au fait que le namespace n'est pas définie dans ton fichier. Donc, tu cherches à utiliser quelque chose qui n'existe pas. Aucun de tes fichiers d'en-tête ne le définit...

[gassi64]

voilà!
donc #include <iostream> dans le .h et using namespace std; dans .cpp

[lui88]

bonjour ,

oui effectivement une erreur d'inattention merci beaucoup a vous .