C++中关于理解dynamic_cast和static_cast区别的一个极其简单的例 dynamic cast 原理

#include <iostream>using namespace std;class color{  public:    virtual void f()     {          cout << "color::f()" << endl;    }   };class red : public color{  public:    void f()     {         cout << "red::f()" << endl;    }   };class blue : public color{  public:    void f()     {         cout << "blue::f()" << endl;    }   };class other{  public:    virtual void f()    {      cout << "other::f()" << endl;    }};int main() {  color *pc = new red;  blue* pb_dynamic = dynamic_cast<blue*>(pc);  blue* pb_static = static_cast<blue*>(pc);  cout << "pb_dynamic: " << pb_dynamic << endl;  cout << "pb_static: " << pb_static << endl;  //pb_dynamic->f();  //pc绑定的是red而不是blue,pb_dynamic为0,调用此句会失败  pb_static->f();  // pc绑定的是red而不是blue,static_cast不识别这些, 而是当做red的函数来处理!  other* _other = new other;  blue* pbo_dynamic = dynamic_cast<blue*>(_other);  //blue* pbo_static = static_cast<blue*>(_other);// _other绑定的是other而不是blue,编译的时候失败  cout << "pbo_dynamic: " << pbo_dynamic << endl;  delete pc;delete _other;  pc = NULL:_other = NULL;  return 0;}//总结:static_cast字面意思是静态转换，编译期间就能判断是否可以转换成功，但是无法识别兄弟指针之间的转换（先提升一个兄弟(red)指针为父指针(color)，再向下转换(blue)）而dynamic_cast是运行时转换，可以编译通过，但是可以与NULL指针的比较来判断是否转换成功！

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