它也可以用来执行上述多种转换的反向转换,例如将void*指针转为typed指针,将pointer-to-base转为pointer-to-derived。但是他无法将const转为non-const,这个只有const-cast才能够办到。 dynamic_cast具有类型检查的功能,比static_cast更安全。 class B{ public: int m_iNum; virtual void foo(); }; class D:publ...
总结下来就是：只要抽象的程度足够，就不需要dynamic_cast。如果抽象程度不够，当然是设计的缺陷。3、但...
它也能够用来运行上述多种转换的反向转换,比如将void*指针转为typed指针。将pointer-to-base转为pointer-to-derived。但无法将const转为non-const(这个仅仅用const_cast才干办到) 使用方法:static_cast< type-id > ( expression_r_r) 该运算符把expression_r_r转换为type-id类型,但没有运行时类型检查来保证转换...
static_cast only allows conversions like int to float or base class pointer to derived class pointer. reinterpret_cast allows anything, that's usually a dangerous thing and normally reinterpret_cast is rarely used, tipically to convert pointers to/from integers or to allow some kind of low ...
cast）有很大的区别，所以 C++ 引入了四种不同的具名转型（named cast）。从技术角度，C 风格转型不能...
c) 可以把空指针转换成目标类型的空指针(null pointer)。 d) 把任何类型的表达式转换成void类型。 注意:static_cast不能转换掉expression的const、volitale或者__unaligned属性。 2) dynamic_cast(带类型检查的转换) 用法:dynamic_cast <typeid> (expression) ...
classDerived:publicBase; Base*a=newBase; Derived*b=static_cast<Derived*>(a); 'static_cast'除了操作类型指针,也能用于执行类型定义的显式的转换,以及基础类型之间的标准转换: 代码: doubled=3.14159265; inti=static_cast<int>(d); 3dynamic_cast ...
Assigning a derived class object to its base class pointer, however, is a passive form of polymorphism; it is using the polymorphism as a transport mechanism. This is the main use of Object, for example, in pre-generic CLR programming. When used passively, the base class pointer chosen for...
_castoperator cannot be used to cast awayconst. You can usestatic_castto cast “down” a hierarchy (from a base to a derived pointer or reference), but the conversion is not checked; the result might not be usable. Astatic_castcannot be used to cast down from a virtual base class....
示例代码: int num = 10; double convertedNum = static_cast(num); Base* basePtr = newDerived(); Derived...当转换的目标类型为指针时,如果转换失败,dynamic_cast会返回空指针;当转换的目标类型为引用时,如果转换失败,...