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support bazel complie this project and format code.
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@@ -1,34 +1,38 @@
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/**
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* @file rtti.cpp
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* @brief 在面向对象程序设计中,有时我们需要在运行时查询一个对象是否能作为某种多态类型使用。与Java的instanceof,以及C#的as、is运算符类似,C++提供了dynamic_cast函数用于动态转型。相比C风格的强制类型转换和C++ reinterpret_cast,dynamic_cast提供了类型安全检查,是一种基于能力查询(Capability Query)的转换,所以在多态类型间进行转换更提倡采用dynamic_cast
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* @brief
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* 在面向对象程序设计中,有时我们需要在运行时查询一个对象是否能作为某种多态类型使用。与Java的instanceof,以及C#的as、is运算符类似,C++提供了dynamic_cast函数用于动态转型。相比C风格的强制类型转换和C++
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* reinterpret_cast,dynamic_cast提供了类型安全检查,是一种基于能力查询(Capability
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* Query)的转换,所以在多态类型间进行转换更提倡采用dynamic_cast
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* @author 光城
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* @version v1
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* @date 2019-07-24
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*/
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// CPP program to illustrate
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// // Run Time Type Identification
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#include<iostream>
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#include<typeinfo>
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using namespace std;
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class B { virtual void fun() {} };
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class D: public B { };
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// CPP program to illustrate
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// Run Time Type Identification
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#include <iostream>
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#include <typeinfo>
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using namespace std;
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class B {
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virtual void fun() {}
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};
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class D : public B {};
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int main()
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{
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B *b = new D; // 向上转型
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B &obj = *b;
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D *d = dynamic_cast<D*>(b); // 向下转型
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if(d != NULL)
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cout << "works"<<endl;
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else
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cout << "cannot cast B* to D*";
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try {
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D& dobj = dynamic_cast<D&>(obj);
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cout << "works"<<endl;
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} catch (bad_cast bc) { // ERROR
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cout<<bc.what()<<endl;
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}
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return 0;
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int main() {
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B *b = new D; // 向上转型
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B &obj = *b;
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D *d = dynamic_cast<D *>(b); // 向下转型
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if (d != NULL)
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cout << "works" << endl;
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else
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cout << "cannot cast B* to D*";
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try {
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D &dobj = dynamic_cast<D &>(obj);
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cout << "works" << endl;
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} catch (bad_cast bc) { // ERROR
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cout << bc.what() << endl;
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}
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return 0;
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}
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