Advanced-C++/C2/Exception-Handling/English

Title of script: Exception Handling in C++

Author: Ashwini Patil

Keywords: Exception handling, try, catch, throw Video tutorial.

Visual Cue	Narration
Slide 1	Welcome to the spoken tutorial on Exception Handling in C++.
Slide 2 Learning Objectives	In this tutorial we will learn, Exception Handling. We will do this with the help of an example.
Slide 3 System requirements	To record this tutorial, I am using Ubuntu OS version 11.10 g++ compiler v. 4.6.1
Slide 4 Introduction to Exception	Let us start with an introduction to exception An exception is a problem that arises during the execution of a program It is a run-time error that a program may detect
Slide 5 Introduction to Exception Handling	Let us move on to exception handling The response given to the problems occured during the execution of the program is known as exception handling. Exception handling allows a program to continue execution. Helps Identifying the problem. Terminates the program in a controlled manner.
Slide 6 Types of Exceptions	Let us see the Types of Exceptions Try Catch Throw We place the error prone code inside a try block Then it is Handled using throw. after this the exception is caught, using catch statement And then it is processed.
Slide 6 Syntax	The syntax for try catch and throw is: Throw: try { // try block } catch (type1 arg) { // catch block } catch (type2 arg) { // catch block } The try block and the catch block, here we pass argument The throw statement can be written inside the try block as well We can have more than try, catch blocks.
	Now let us see an example on exception handling. I have the code, i will explain it to you.
	our filename is exception.cpp In this program we will solve the divide by zero error using exception handling. Let us go through the code
Highlight #include <iostream> using namespace std;	This is our header file as iostream. Here we are using the std namespace.
Highlight double division(int a, int b) { if( b == 0 ) { throw "Division by zero condition!"; } return (a/b); }	Here we have function division with argument as int a and int b. We check whether b ==0. If true, we throw an exception division by zero condition The function returns division of a and b
Highlight int main()	This is our main function.
Highlight int x,y; double z; cout<<"Enter value of x and y\n"; cin>>x>>y;	In this we have declared three variables as x, y and z. Here we accept the values of x and y.
Highlight try { z = division(x, y); cout << z<<"\n"; }	This is our try block Here we have called the function division. And stored the result in z. Then we print the value of z.
Highlight catch (const char* msg) {	This is our catch block. In this we pass an argument msg as a character constant.
Highlight cout << msg << endl; }	Then we print the msg.
Highlight return 0;	And this is our return statement.
	Let us execute the program
Open the terminal Ctrl, Alt and T keys simultaneously	open the terminal by pressing Ctrl, Alt and T keys simultaneously on your keyboard
Type g++ exception.cpp -o exp To execute Type ./exp	To compile type g++ exception.cpp -o ex To execute Type ./ex
Highlight Output	Here we see, Enter the value of x and y: I will first enter as 3 and 0 The output is displayed as: Division by zero condition Let us compile again Press the up arrow key twice Press enter, again press the up arrow key twice Enter value of x and y i will give as 8 and 2 The output is 4
	This is how the try catch block works.
Switch back to the slides	This brings us to the end of this tutorial. Let us come back to our slides
Slide 7 Summary	Let us summarize, In this tutorial, we have seen, Exception Handling Try Catch Throw blocks
Slide 6 Assignment	As an assignment Display the age of employess. Throw an exception to check that the age is not less than 15.
Slide 8 About the Spoken Tutorial Project	Watch the video available at the link shown It summarizes the Spoken Tutorial project If you do not have good bandwidth, you can download and watch it
Slide 9 Spoken Tutorial Workshops	The Spoken Tutorial Project Team Conducts workshops using spoken tutorials Gives certificates to those who pass an online test For more details, please write to, contact@spoken-tutorial.org
Slide Number 10 Acknowledgement	Spoken Tutorial Project is a part of the Talk to a Teacher project It is supported by the National Mission on Education through ICT, MHRD, Government of India More information on this Mission is available at: http://spoken-tutorial.org\NMEICT-Intro
	This is Ashwini Patil from IIT Bombay signing off Thank You for joining.

Contributors and Content Editors

Ashwini