- If …else statement is an extension of simple if statement.
- When we have two different path to follow,then simple if statement cannot be useful because if provides a single path to follow.
- In such situation if…else statement is more suitable.
- If…else statement helps to perform different actions based on true or false condition.
- It has the following form:
Syntax:
if (condition)
{
//true block;
}
else
{
//false block;
}
- If given expression evaluates to true then true block will be executed and if condition is false then else block will be execute.
- In any situation only one block will be executed that is if condition is true then true block will be executed and else block will be skipped.
- Similarly, if condition is false then else block will be executed and true block will be skipped.
- When if and else statement has a single statement then brackets are not required but it is necessary when it contain two or more statements.
- The above code fragment (part) will display odd or even number depending on the condition.
Example:
<?php
// Program to check if number is even or odd.
$n = 10 ;
if($n % 2 == 0)
{
echo "Number is even" ;
}
else
{
echo "Number is odd" ;
}
?>
Conditional Statement:
- Conditional statement is written using conditional operator also known as ternary operator.
- The format of the conditional operator is as follow:
(Condition)? Statement-1 : Statement-2
- It takes three operands.
- If condition is true then statement-1 will be executed otherwise statement-2 will be executed.
- We can also represent the condition for assignment operation like:
variable = (Condition)? Value-1 : Value-2
- Here if condition is true then variable has assigned the value-1 otherwise it has assigned the value-2
$sales = 70000 ;
$commission = (sales > 50000) ? 2000 : 0; // assign 2000 to commission
- In above example if sale is > 50000 then commission value will be 2000 otherwise it will be zero.
- It is similar to if…else statement and we can rewrite conditional statement using if…else statement as follow:
<?php
if( sales > 50000)
commission = 2000 ;
else
commission = 0 ;
?>