Explain the concepts of throwing and catching exceptions

C++ provides a mechanism to handle exceptions which occurs at runtime. C++ uses the keywords – throw, catch and try to handle exception mechanism. An entity called an exception class need to be created.

The application should have a separate section called catch block. The code in which an exception is predicted is authored in the try block.

The following code illustrates to handle the exception.

#include
class Excep {
public:
      const char* error;
      Excep(const char* arg) : error(arg) { }
};

class Test {
   public:
        int i;
    // A function try block with a member initializer
      Test() try : i(0) {
             throw Excep("Exception thrown in A()");
       }
       catch (Excep& e) {
             cout << e.error << endl;
       }
};

// A function try block
void f() try {
      throw E("Exception thrown in f()");
}
catch (Excep& e) {
     cout << e.error << endl;
}
void g() {
     throw Excep("Exception thrown in g()");
}

int main() {
   f();
    // A try block
    try {
       g();
    }
     catch (Excep& e) {
          cout << e.error << endl;
     }
      try {
           Test x;
      }
      catch(...) { }
}

The following is the output of the above example:
Exception thrown in f()
Exception thrown in g()
Exception thrown in A().