Overloading exception::what()

[TheDestroyer]

Hello guys,

I've created my own exception class which is inherited from the class std::exception. Actually I'm not sure why I'm doing this, but I've seen everyone doing it, and I think it's the way to handle the errors of the standard library with the errors of my programs.

Anyway, the problem is, I would like to overload the function std::exception::what(), so that in case I don't catch the exception it displays what the error is from my program. So what I did is the following:

In the prototypes of the class I defined:

class Exception_sam_base : public exception
{
public:

    Exception_sam_base();
    Exception_sam_base(string ErrorMsg);
    Exception_sam_base(const Exception_sam_base& orig);
    virtual ~Exception_sam_base() throw();
    static string ProgramName;
    void setErrorMessage(string str);
    void setErrorDetails(string str);
    void setErrorID(long int value);
    void setResolutionMessage(string str);
    vector< vector<string> >& VariableList();
    virtual const char* what();
private:
    string ErrorMessage;
...
}

and in the definition I defined the overloaded version of my what()

const char* Exception_sam_base::what()
{
    return this->ErrorMessage.c_str();
}

So now I expect when a throw happens without being catched, the new version of what() will be called and write in the console what the error is. But it doesn't happen!

Is it right the way I'm thinking? or have I missed something?

Thank you :-)

[Bazzy]

The proper prototype to override exception::what() is const char* what() const throw()
But if you want to be sure that what() is displayed, you should catch the exception

[TheDestroyer]

ah! thanks a lot buddy! it has worked :D

I'm grateful :)