下面的代码来自于VC++ 8.0里面的源码：
下面的例程来自Exceptional C++，Item 37：
// Example 2: Using an auto_ptr//void g()
{
T* pt1 = new T; // right now, we own the allocated object // pass ownership to an auto_ptr auto_ptr<T> pt2( pt1 ); // use the auto_ptr the same way // we'd use a simple pointer *pt2 = 12; // same as "*pt1 = 12;" pt2->SomeFunc(); // same as "pt1->SomeFunc();" // use get() to see the pointer value assert( pt1 == pt2.get() ); // use release() to take back ownership T* pt3 = pt2.release(); // delete the object ourselves, since now // no auto_ptr owns it any more delete pt3;
} // pt2 doesn't own any pointer, and so won't // try to delete it... OK, no double delete // Example 3: Using reset()//void h(){ auto_ptr<T> pt( new T(1) ); pt.reset( new T(2) ); // deletes the first T that was // allocated with "new T(1)"} // finally, pt goes out of scope and // the second T is also deleted auto_ptr(auto_ptr<_Ty>& _Right) _THROW0() : _Myptr(_Right.release()) { // construct by assuming pointer from _Right auto_ptr } template<class _Other> auto_ptr<_Ty>& operator=(auto_ptr<_Other>& _Right) _THROW0() { // assign compatible _Right (assume pointer) reset(_Right.release()); return (*this); }// Example 6: Never try to do work through// a non-owning auto_ptr//void f(){ auto_ptr<T> pt1( new T ); auto_ptr<T> pt2; pt2 = pt1; // now pt2 owns the pointer, and // pt1 does not pt1->DoSomething(); // error: following a null pointer}
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