Tuesday Aug 22, 2006
Introducing the if else construct, while loops and other control loops that will help you in adding logic to your code. Okay our task is to make our programs intelligent I mean let's learn how to add decision making logic in our code. PHP like all other good programming languages provides logic and looping by using if and while statements.

Introducing the IF construct
The if construct is one of the basic decision making construct, it is also included in PHP. It allows the conditional execution of code fragments. PHP features an if structure that is similar to that of the 'C' language.

The syntax for if else structure is
If (conditions)
{
// Code if condition is true
}
else
{
// Code if condition is false
}


Let me give you an example, let's assume that you and your friend are planning to go for a movie and you need more than 20 bucks to go to the movie, if you have less than 20 bucks you can't go, if you would have written a program the PHP equivalent code would be something like this

<?php
$money = 15;

if($money > 20)
{
echo "Hey we can go to the movie, we have $money bucks";
}
else
{
echo "Oops we can't go to the movie, we have only $money bucks";
}

?>


We have used the Comparison operator > Greater than above to check if $money > 20

PHP supports many different comparison operators that allow us to add logic in our code.

The comparison operators are listed below:
$a == $b $a is equal to $b
$a != $b $a is not equal to $b

$a < $b $a is less than $b
$a > $b $a is greater than $b
$a <= $b $a is less than or equal to $b
$a >= $b $a is greater than or equal to $b