#include using namespace std; class Foo { public: Foo ( void ); Foo ( int var ); //违背1 int getVar ( void ); ~Foo ( void ); private: int a; }; Foo::Foo ( void ) { a = 0; } Foo::Foo ( int var ) { a = var; } int Foo::getVar ( void ) { return a; } Foo::~Foo ( void ) { } void f ( Foo ); int main ( void ) { int i = 1; f ( i ); return ( 0 ); } void f ( Foo thef ) { int j; //... j = thef.getVar ( ); }