C/C++ Programming Techniques
ET2031/ ET2031E
Lecturer: PhD. DO Thi Ngoc Diep
SCHOOL OF ELECTRICAL AND ELECTRONIC ENGINEERING
HANOI UNIVERSITY OF SCIENCE AND TECHNOLOGY
Chapter 8: Exceptions
3
Content
•Introduction
•Trapping and catching mechanism
•Exception handling in C++
4
Introduction
•An exception is an event that occurs during program execution
disrupting the normal flow of the program
•Exception is a special error
•Due to wrong programming
•Due to incorrect data input, due to system status (overflow)
•etc.
•When an exception occurs, if not handled, the program
immediately terminates and returns control to the operating
system.
•Allocated resources are not released resource wasting
•Without closing the file file cannot be accessed/corrupted
5
Introduction
•Traditional error handling
•Write the handling code where the error occurs
•Make the program messed up, There is not always enough information to process,
It is not necessary to process
•Transmit the state to the upper level
•Via parameter, return value or global variable, Easy to mistake, Still confusing
•Defect: Difficult to control all cases
•Arithmetic errors, memory errors, Programmers often forget to handle errors,
Human nature: Inexperienced, deliberately omitted
•In C: there are no preventive measures as well as simplified error
handling completely dependent on the programmer
•Error handling in C++: introduced a "trap and catch" mechanism
(try .. catch .. throw) to enhance the ability as well as simplify error
handling
