Course Content

Introduction to PHP

1. First Acquaintance

Features of the PHP Language First Application Comments in PHP Basic Math Operations Math Expressions

2. Variables and Data Types

Data Types Variables Strings Boolean Comparison Operations

3. Conditional Statements

If Statement Else Statement Else If Statement Switch-Case Statement

4. Arrays

Creating Arrays Indexes Associative Arrays Adding and Removing Elements in Arrays

5. Loops

Loops Сoncept While-Loops Do-While For-Loops Increment and Decrement

Indexes

Let's consider how to work with arrays. First, let's understand how to access specific elements in an array.

To access a specific element in an array, use square brackets with the index. Remember that the index is not the actual position of the element, as indexing in PHP starts from 0. Let's look at an example for clarity.

The index is always one less than the actual position. For example, we can retrieve several elements from an array in the example below:

main


              1234567
            
<?php
// Initial array
$site = ["c", "o", "d", "e", "f", "i", "n", "i", "t", "y"];

// Getting letters 'o' and 'y'
echo $site[1] . " " . $site[9]; // outputs 'o y'
?>

In this example, the array $site contains the letters of the word "codefinity". We use numerical indices to access specific letters.

String Indexes

In PHP, just like arrays, strings also have indexes starting from zero. This means you can access each individual character of a string by its index, similar to how you work with elements in an array. For example, in the string $string = "Hello";, the character 'H' has index 0, 'e' has index 1, and so on. You can access characters using square brackets like $string[0] will give you 'H', or curly braces like $string{0} will also give you 'H'. This allows you to manipulate individual characters in a string as easily as elements in an array.

main


              1234567
            
<?php
// Initial array
$string = "Hello";

// Getting letter 'H'
echo $string[0]; // outputs 'H'
?>

Task

Fill in the blanks in the code. Access the second element of the array ($array) and print it to the screen.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Everything was clear?

Thanks for your feedback!

Section 4. Chapter 2

Indexes

Let's consider how to work with arrays. First, let's understand how to access specific elements in an array.

The index is always one less than the actual position. For example, we can retrieve several elements from an array in the example below:

main


              1234567
            
<?php
// Initial array
$site = ["c", "o", "d", "e", "f", "i", "n", "i", "t", "y"];

// Getting letters 'o' and 'y'
echo $site[1] . " " . $site[9]; // outputs 'o y'
?>

In this example, the array $site contains the letters of the word "codefinity". We use numerical indices to access specific letters.

String Indexes

main


              1234567
            
<?php
// Initial array
$string = "Hello";

// Getting letter 'H'
echo $string[0]; // outputs 'H'
?>

Task

Fill in the blanks in the code. Access the second element of the array ($array) and print it to the screen.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Everything was clear?

Thanks for your feedback!

Section 4. Chapter 2

Indexes

Let's consider how to work with arrays. First, let's understand how to access specific elements in an array.

The index is always one less than the actual position. For example, we can retrieve several elements from an array in the example below:

main


              1234567
            
<?php
// Initial array
$site = ["c", "o", "d", "e", "f", "i", "n", "i", "t", "y"];

// Getting letters 'o' and 'y'
echo $site[1] . " " . $site[9]; // outputs 'o y'
?>

In this example, the array $site contains the letters of the word "codefinity". We use numerical indices to access specific letters.

String Indexes

main


              1234567
            
<?php
// Initial array
$string = "Hello";

// Getting letter 'H'
echo $string[0]; // outputs 'H'
?>

Task

Fill in the blanks in the code. Access the second element of the array ($array) and print it to the screen.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Everything was clear?

Thanks for your feedback!

Let's consider how to work with arrays. First, let's understand how to access specific elements in an array.

The index is always one less than the actual position. For example, we can retrieve several elements from an array in the example below:

main


              1234567
            
<?php
// Initial array
$site = ["c", "o", "d", "e", "f", "i", "n", "i", "t", "y"];

// Getting letters 'o' and 'y'
echo $site[1] . " " . $site[9]; // outputs 'o y'
?>

In this example, the array $site contains the letters of the word "codefinity". We use numerical indices to access specific letters.

String Indexes

main


              1234567
            
<?php
// Initial array
$string = "Hello";

// Getting letter 'H'
echo $string[0]; // outputs 'H'
?>

Task

Fill in the blanks in the code. Access the second element of the array ($array) and print it to the screen.

Switch to desktop for real-world practiceContinue from where you are using one of the options below

Section 4. Chapter 2

Switch to desktop for real-world practiceContinue from where you are using one of the options below