C++中的异常处理（上）

Posted 2021-10-03 学习只为旅行

#include <iostream>
#include <string>

using namespace std;

double divide(double a, double b)
{
    const double delta = 0.000000000000001;
    double ret = 0;
    
    if( !((-delta < b) && (b < delta)) )
    {
        ret = a / b;
    }
    else
    {
        throw 0;
    }
    
    return ret;
}

int main(int argc, char *argv[])
{    
    try
    {
        double r = divide(1, 0);
            
        cout << "r = " << r << endl;
    }
    catch(...)		//...代表
    {
        cout << "Divided by zero..." << endl;
    }
    
    return 0;
}

打印：Divided by zero…

#include <iostream>
#include <string>

using namespace std;

void Demo1()
{
    try
    {   
        throw 'c';
    }
    catch(char c)
    {
        cout << "catch(char c)" << endl;
    }
    catch(short c)
    {
        cout << "catch(short c)" << endl;
    }
    catch(double c)
    {
        cout << "catch(double c)" << endl;
    }
    catch(...)
    {
        cout << "catch(...)" << endl;
    }
}

void Demo2()
{
    throw string("D.T.Software");
}

int main(int argc, char *argv[])
{    
    Demo1();
    
    try
    {
        Demo2();
    }
    catch(char* s)
    {
        cout << "catch(char *s)" << endl;
    }
    catch(const char* cs)
    {
        cout << "catch(const char *cs)" << endl;
    }
    catch(string ss)
    {
        cout << "catch(string ss)" << endl;
    }
    
    return 0;
}

throw “shdjkaha”;这句代码抛出的异常类型为const char* 类型，所以catch可以写const char*的。

小结