Perl IF statement

Author：Eve Cole Update Time：2024-12-24 16:36:01

A Perl if statement consists of a Boolean expression followed by one or more statements.

grammar

The syntax format is as follows:

 if(boolean_expression){ #Execute when boolean_expression is true}

If the boolean_expression is true, the code block within the if statement will be executed. If the Boolean expression is false, the first set of code after the end of the if statement (after the closing bracket) will be executed.

flow chart

Example

#!/usr/bin/perl $a = 10 ; # Use if statement to judge Boolean expression if ( $a < 20 ) { #Executed when the Boolean expression is true printf " a is less than 20 n " ; } print " The value of a is: $a n " ; $a = " " ; # Use if statements to determine Boolean expressions if ( $a ) { #iExecuted when the Boolean expression is true printf " Variable a is true n " ; } print " The value of a is: $a n " ;

Executing the above program, the output result is:

 The value of a less than 20a is: The value of 10a is: