Amazing slide show about Switch Case in Programming Language C. It's helpfull for engineering students .

1. 1
Switch Case

2. 2
 Switch Case
 Flow Chart of Switch Case
 Creating Menus
 Switch – syntax
 Switch Example
 Switch Default
 To Switch or not To Switch
 Uses of Switch Case
 Summary
0utlInes

3. Switch Case
3
The last statement of each case in the
switch should almost always be a break.
The break causes program control to
jump to the closing brace of the switch
structure.
Without the break, the code flows into
the next case. This is almost never
what you want.
A switch statement will compile without
a default case, but always consider
using one.

4. Flow Chart of Switch
Case
4

5. 5
Creating Menus
When you want to give your user a
choice on what to do next, you can
display a set of choices (a menu).
The user then enters his or her
choice. You must validate the
choice to make sure it is valid
before you continue the program!

6. Switch - Syntax
6
 The general syntax of a switch case is:
switch
and
case
are
reserved
words
switch ( expression ){
case value1 :
statement-list1
case value2 :
statement-list2
case value3 :
statement-list3
case ...
}
If expression
matches value3,
control jumps
to here

7. Switch Example
7
Example of the switch case:
switch
(option){
case 'A':
aCount++;
break;
case 'B':
bCount++;
break;
case 'C':
cCount++;
break;
}

8. Switch Example
8
switch ( day )
{
case 0: printf (“Sundayn”) ;
break ;
case 1: printf (“Mondayn”) ;
break ;
case 2: printf (“Tuesdayn”) ;
break ;
case 3: printf (“Wednesdayn”) ;
break ;
case 4: printf (“Thursdayn”) ;
break ;
case 5: printf (“Fridayn”) ;
break ;
case 6: printf (“Saturdayn”) ;
break ;
default: printf (“Error -- invalid day.n”) ;
break ;
}
Is this structure
more efficient than
the equivalent
nested if-else
structure?

9. Switch - Default
9
A switch statement can have an optional
default case
The default case has no associated value
and simply uses the reserved word default
If the default case is present, control will
transfer to it if no other case value
matches
If there is no default case, and no other
value matches, control falls through to the
statement after the switch

10. 10
Switch With Default Case Example
switch (option){
case 'A':
aCount++;
break;
case 'B':
bCount++;
break;
case 'C':
cCount++;
break;
default:
otherCount++;
break;
}

11. 11
To Switch or not To Switch
 The expression of a switch statement must
result in an integral type, meaning an integer
(byte, short, int, long) or a char
 It cannot be a boolean value or a floating point
value (float or double)
 The implicit boolean condition in a switch
statement is equality
 You cannot perform relational checks with a
switch statement

12. 12
Why Use a switch case?
A nested if-else structure is just as
efficient as a switch case.
However, a switch case may be
easier to read.
Also, it is easier to add new cases
to a switch case than to a nested if-
else structure.

13. 13
Summary
 The break statement can be used as the last
statement in each case's statement list
 A break statement causes control to transfer to
the end of the switch statement
 If a break statement is not used, the flow of control
will continue into the next case

14. THANKS
TO
ALL