Use of “switch” as a conditional
A switch statement allows a variable to be tested for equality against a list of values. Each value is called a case, and the variable being switched on is checked for each case.
Syntax:
The syntax for a switch statement in C++ is as follows:
switch(expression){ case constant-expression : statement(s); break; //optional case constant-expression : statement(s); break; //optional // you can have any number of case statements. default : //Optional statement(s); }
The following rules apply to a switch statement:
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The expression used in a switch statement must have an integral or enumerated type, or be of a class type in which the class has a single conversion function to an integral or enumerated type.
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You can have any number of case statements within a switch. Each case is followed by the value to be compared to and a colon.
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The constant-expression for a case must be the same data type as the variable in the switch, and it must be a constant or a literal.
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When the variable being switched on is equal to a case, the statements following that case will execute until a break statement is reached.
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When a break statement is reached, the switch terminates, and the flow of control jumps to the next line following the switch statement.
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Not every case needs to contain a break. If no break appears, the flow of control will fall throughto subsequent cases until a break is reached.
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A switch statement can have an optional default case, which must appear at the end of the switch. The default case can be used for performing a task when none of the cases is true. No break is needed in the default case.
