C++从入门到精通——异常处理

• 捕捉异常
• throw: 问题出现时，抛出异常
• catch:用于捕捉异常
• try：标识即将被激活的异常

#include <iostream>
using namespace std;
double division(int a,int b){
  if(b==0){
      throw "除数不能为0";
  }
  return a/b;
};

int main(){

    int x=50;
    int y = 0;
    double z = 0;
    try {
        z = division(x,y);
        cout<<"z is :"<<z<<endl;
    }// 抛出指定的异常
    catch (const char* msg){
        cerr<<msg<<endl;
    }catch (const exception e){
        return 0 ;
    }
    return 0;
}

• 自定义异常

#include <iostream>
#include <exception>
using namespace std;
double division(int a,int b){
  if(b==0){
      throw "除数不能为0";
  }
  return a/b;
};

struct MyException:public exception{

    const char *what () const throw(){
        return "C++ Exception";
    }

};
int main(){

    int x=50;
    int y = 0;
    double z = 0;
    try {
        throw MyException();
    }catch(MyException& e){
        cout<<e.what()<<endl;
    }


    try {
        z = division(x,y);
        cout<<"z is :"<<z<<endl;
    }// 抛出指定的异常
    catch (const char* msg){
        cerr<<msg<<endl;
    }catch (const exception &e){
        return 0 ;
    }
    return 0;
}