Exception handling
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Exception handling in C++ allows programs to deal with abnormal or unexpected behaviors during execution. It uses three keywords - try, catch, and throw. The try block defines the code that might cause exceptions. If an exception occurs, the program flow moves to the catch block to handle it. Multiple catch blocks can be chained to handle different exception types. The throw keyword transfers control from the try block to the catch block when an exception happens.
Exception handling
- 2. An exception is a situation which is unusual for a program that is being processed What is Exception Handling ? The ability to deal with a programs eventual abnormal behavior is called Exception handling.
- 3. C++ provides three keywords to 1. Try (Trying the normal flow) 2. Catch (Catching Errors) 3. Throw (Throwing an error) handle an exception.
- 4. Syntax: try {Behavior} Try (Trying the normal flow) It lets the compiler know that you are anticipating an abnormal behavior and will try to deal with it.
- 5. Syntax: catch(Argument) {WhatToDo} Catch (Catching Errors) During the flow of the program as part of the try section if an abnormal behavior occurs, instead of letting the program crash you can transfer the flow of the program to another section that can deal with it and that section is Catch Section.
- 6. try { CCoommbbiinneedd wwiitthh tthhee ttrryy bblloocckk,, tthhee ssyynnttaaxx ooff aann eexxcceeppttiioonn wwoouulldd bbee:: // Try the program flow } catch(Argument) { // Catch the exception }
- 7. We can also chain multiple handlers (catch expressions), each one with a different parameter type try { // code here } catch (int param) { cout << "int exception"; } catch (char param) { cout << "char exception"; } catch (...) { cout << "default exception"; }
- 8. The transfer of control from the try block to the catch clause is carried by the throw keyword. Eg : throw ; throw "Positive Number Required"; TThhrrooww ((TThhrroowwiinngg aann eerrrroorr))
- 9. NNooww LLeett''ss FFaaccee SSoommee EExxcceeppttiioonnss......
- 10. #include <iostream> int main() { double Number1, Number2, Result; // Request two numbers from the user cout << "Please provide two numbersn"; try { cout << "First Number: "; cin >> Number1; cout << "Second Number: "; cin >> Number2;
- 11. if( Number2 == 0 ) throw"Cant divide by zero"; // Perform a division and display the result Result = Number1 / Number2; cout << "n" << Number1 << " / " << Number2 << " = " << Result << "nn"; } catch(const char* Message) { cout << "Error: " << Message; } getch(); return 0; }
- 12. WWhheenn YYoouu FFaaccee AAnn EExxcceeppttiioonn
- 13. NNooww LLeett''ss FFaaccee AAnnootthheerr EExxcceeppttiioonn......
- 14. #include<conio.h> #include<iostream.h> class factorial { int i,fact; public: void facto(int n) { fact=1; for(i=1;i<=n;i++) { fact=fact*i; } cout<<"Factorial of a given no. is"<<fact; } };
- 15. int main() { clrscr(); int n; factorial f; cout<<"Enter no.n"; cin>>n; try { if(n<0) throw"Please Enter natural no !!!"; f.facto(n); } catch(const char *message) { cout<<"Error:"<<message; } getch(); return 0; }
- 16. WWhheenn YYoouu FFaaccee AAnn EExxcceeppttiioonn
- 18. Q1. Identify tthhee ccoorrrreecctt ssttaatteemmeenntt ?? 1. There must not be any code between the trys closing bracket and the catch section. 2. There can be any code between the trys closing bracket and the catch section. 3. There may be any code between the trys closing bracket and the catch section. 4. There must be any code between the trys closing bracket and the catch section.
- 19. QQ22.. TThheerree ccaann bbee mmuullttiippllee ccaattcchh bblloocckk iinn pprrooggrraamm ?? 1. True 2. False
- 20. QQ33.. WWhhiicchh ooff tthheessee llaanngguuaaggee ddooeess nnoott ssuuppppoorrtt EExxcceeppttiioonn hhaannddlliinngg ?? 1. Java 2. C++ 3. C
- 21. Q4. Which of tthheessee ssttaatteemmeennttss iiss ccoorrrreecctt ?? 1. Try 3. Try { throw; { throw }; }; 2. Try 4. Try { throw; { throw } }
- 22. Q5. WWhhiicchh ooff tthheessee ssttaatteemmeennttss iiss nnoott ccoorrrreecctt ?? 1. Catch(.){} 2. Catch(){} 3. Catch(const char *message){} 4. Catch(int message){}