static_cast 与 boost::shared_ptr？
与 boost::shared_ptr 等效的 static_cast 是什么？
换句话说，
Base* b = new Derived();
Derived* d = static_cast<Derived*>(b);
使用 shared_ptr 时我该如何重写以下内容？
boost::shared_ptr<Base> b(new Derived());
boost::shared_ptr<Derived> d = ???
What is the equivalent of a static_cast with boost::shared_ptr?
In other words, how do I have to rewrite the following
Base* b = new Derived();
Derived* d = static_cast<Derived*>(b);
when using shared_ptr?
boost::shared_ptr<Base> b(new Derived());
boost::shared_ptr<Derived> d = ???
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使用boost::static_pointer_cast：
Use
boost::static_pointer_cast:智能指针共有三个强制转换运算符：
static_pointer_cast、dynamic_pointer_cast和const_pointer_cast。 它们位于命名空间boost（由std::tr1（由 Boost 提供）中或通过编译器的 TR1 实现）。There are three cast operators for smart pointers:
static_pointer_cast,dynamic_pointer_cast, andconst_pointer_cast. They are either in namespaceboost(provided by<boost/shared_ptr.hpp>) or namespacestd::tr1(provided either by Boost or by your compiler's TR1 implementation).作为评论：如果 Derived 实际上是从 Base 派生的，那么您应该使用dynamic_pointer_cast 而不是静态强制转换。 系统将有机会检测到您的演员表何时/是否不正确。
As a comment: if Derived does in fact derive from Base, then you should use a dynamic_pointer_cast rather than static casts. The system will have a chance of detecting when/if your cast is not correct.
值得一提的是，Boost 提供的转换算子数量与 TR1 的实现存在差异。
TR1没有定义第三个运算符const_pointer_cast()
It is worth to mention that the there is difference in the number of casting operators provided by Boost and implementations of TR1.
The TR1 does not define the third operator const_pointer_cast()