PHP Basics

PHP code is enclosed within special tags, allowing the server to identify and execute it. The standard PHP opening tag is <?php, and the closing tag is ?>. Let’s begin with a classic “Hello, World!” example:

<?php
echo “Hello, World!”;
?>

In PHP, variables are containers for storing data. The beauty of PHP lies in its loose typing, where variables adapt to the data assigned to them. Here’s an example demonstrating variables and their dynamic data types:

<?php
$name = “Alice”; // String
$age = 30; // Integer
$isStudent = true; // Boolean
$price = 19.99; // Float (decimal)
?>

Operators in PHP perform various operations, from arithmetic to comparisons and logical evaluations. Take a look at this example illustrating different types of operators:

<?php
$x = 10;
$y = 5;

$sum = $x + $y; // Addition
$isGreater = $x > $y; // Comparison (greater than)
$isTrue = true && false; // Logical (AND)
?>

Conditional statements are crucial for decision-making in PHP. They execute different code blocks based on specified conditions. Here’s an example using if, else, and elseif statements:

<?php
$hour = date(‘H’);

if ($hour < 12) {
echo “Good morning!”;
} elseif ($hour < 18) {
echo “Good afternoon!”;
} else {
echo “Good evening!”;
}
?>

Loops enable repetitive execution of code until a specific condition is met. PHP offers four main types of loops. Let’s explore a simple for loop example:

<?php
for ($i = 1; $i <= 5; $i++) {
echo “Number: $i <br>”;
}
?>

PHP boasts an extensive collection of built-in functions to simplify coding tasks. They range from string manipulation to mathematical operations. Here’s an example using the strlen() function to find the length of a string:

<?php
$text = “Hello, PHP!”;
$length = strlen($text);
echo “Length of the string: $length”;
?>