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int i;
double d;
i = (int) d;
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i = int (d);
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reinterpret_cast<new_type>(expression)
dynamic_cast<new_type>(expression)
static_cast<new_type>(expression)
const_cast<new_type>(expression)
1 reinterpret_cast
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class A {};
class B {};
A * a = new A;
B * b = reinterpret_cast<B *>(a);
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2 static_cast
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class Base {};
class Derived : public Base {};
Base *a = new Base;
Derived *b = static_cast<Derived *>(a);
'static_cast'³ýÁ˲Ù×÷ÀàÐÍÖ¸Õ룬ҲÄÜÓÃÓÚÖ´ÐÐÀàÐͶ¨ÒåµÄÏÔʽµÄת»»£¬ÒÔ¼°»ù´¡ÀàÐÍÖ®¼äµÄ±ê׼ת»»:
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double d = 3.14159265;
int i = static_c
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