PHP, MySQL, & JavaScript All-In-One For Dummies E-Book

Richard Blum

• Herausgeber: John Wiley & Sons
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 952

Veröffentlichungsjahr: 2025

Beschreibung

Learn the essentials of creating web apps with some of the most popular programming languages

PHP, MySQL, & JavaScript All-in-One For Dummies bundles the essentials of coding in some of the most in-demand web development languages. You'll learn to create your own data-driven web applications and interactive web content. The three powerful languages covered in this book form the backbone of top online apps like Wikipedia and Etsy. Paired with the basics of HTML and CSS—also covered in this All-in-One Dummies guide—you can make dynamic websites with a variety of elements. This book makes it easy to get started. You'll also find coverage of advanced skills, as well as resources you'll appreciate when you're ready to level up.

• Get beginner-friendly instructions and clear explanations of how to program websites in common languages
• Understand the basics of object-oriented programming, interacting with databases, and connecting front- and back-end code
• Learn how to work according to popular DevOps principles, including containers and microservices
• Troubleshoot problems in your code and avoid common web development mistakes

This All-in-One is a great value for new programmers looking to pick up web development skills, as well as those with more experience who want to expand to building web apps.

Leseprobe

PHP, MySQL®, & JavaScript® All-in-One For Dummies®

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Table of Contents

Cover

Table of Contents

Title Page

Copyright

Introduction

About This Book

Foolish Assumptions

Icons Used in This Book

Beyond the Book

Where to Go from Here

Book 1: Getting Started with Web Programming

Chapter 1: Examining the Pieces of Web Programming

Creating a Simple Web Page

Creating a Dynamic Web Page

Storing Content

Chapter 2: Using a Web Server

Recognizing What’s Required

Considering Your Server Options

Tweaking the Servers

Building a Development Environment

Book 2: HTML5 and CSS3

Chapter 1: The Basics of HTML5

Diving into Document Structure

Looking at the Basic HTML5 Elements

Marking Your Text

Working with Characters

Making a List (And Checking It Twice)

Building Tables

Chapter 2: The Basics of CSS3

Understanding Styles

Styling Text

Working with the Box Model

Styling Tables

Positioning Elements

Chapter 3: HTML5 Forms

Understanding HTML5 Forms

Using Input Fields

Adding a Text Area

Using Drop-Down Lists

Enhancing HTML5 Forms

Using HTML5 Data Validation

Chapter 4: Advanced CSS3

Rounding Your Corners

Using Border Images

Looking at the CSS3 Colors

Playing with Color Gradients

Adding Shadows

Creating Fonts

Handling Media Queries

Chapter 5: HTML5 and Multimedia

Working with Images

Playing Audio

Watching Videos

Getting Help from Streamers

Book 3: JavaScript

Chapter 1: Introducing JavaScript

Learning about the Power of JavaScript

Including JavaScript in Your HTML Code

The Basics of JavaScript

Controlling Program Flow

Working with Functions

Chapter 2: Advanced JavaScript Coding

The Document Object Model

Finding Your Elements

Working with DOM Form Data

Chapter 3: Using jQuery

What Is jQuery?

Loading the jQuery Library

jQuery Basics

Replacing Data

Changing Styles

Changing the DOM

Playing with Animation

Chapter 4: Reacting to Events with JavaScript and jQuery

What Are Events?

JavaScript and Events

jQuery and Events

Chapter 5: Troubleshooting JavaScript Programs

Identifying Errors

Working with Browser Developer Tools

Working Around Errors

Book 4: PHP

Chapter 1: Understanding PHP Basics

Why Use PHP?

Using PHP

Working with PHP Variables

Utilizing PHP Operators

Including Files

Chapter 2: PHP Flow Control

Using Logic Control

Looping

Building Your Own Functions

Event-Driven PHP

Chapter 3: PHP Libraries

Understanding How PHP Uses Libraries

Tapping Into Text Functions

Working with Math Functions

Dealing with Date and Time Functions

Accessing Image-Handling Functions

Chapter 4: Considering PHP Security

Exploring PHP Vulnerabilities

PHP Vulnerability Solutions

Chapter 5: Object-Oriented PHP Programming

Understanding the Basics of Object-Oriented Programming

Using Magic Class Methods

Loading Classes

Extending Classes

Chapter 6: Sessions and Carts

Storing Persistent Data

Interacting with Cookies in PHP

Working with Sessions in PHP

Creating Online Shopping Carts

Book 5: MySQL

Chapter 1: Introducing MySQL

Understanding the Purpose of a Database

Presenting MySQL

Advanced MySQL Features

Chapter 2: Administering MySQL

MySQL Administration Tools

Managing User Accounts

Chapter 3: Designing and Building a Database

Managing Your Data

Creating Databases

Building Tables

Chapter 4: Using the Database

Working with Data

Searching for Data

Playing It Safe with Data

Chapter 5: Communicating with the Database from PHP Scripts

Database Support in PHP

Using the mysqli Library

Putting It All Together

Book 6: Creating Object-Oriented Programs

Chapter 1: Designing an Object-Oriented Application

Determining Application Requirements

Creating the Application Database

Designing the Application Objects

Designing the Application Layout

Coding the Website Layout

Chapter 2: Implementing an Object-Oriented Application

Working with Events

Bidder Object Events

Responding to Item Object Events

Logging Out of a Web Application

Testing Web Applications

Chapter 3: Using AJAX

Getting to Know AJAX

Communicating Using JavaScript

Using the jQuery AJAX Library

Transferring Data in AJAX

Modifying the AuctionHelper Application

Chapter 4: Extending WordPress

Getting Acquainted with WordPress

Installing WordPress

Examining the Dashboard

Customizing Your WordPress Website

Exploring the World of Plugins

Creating Your Own Widget

Book 7: Using PHP Frameworks

Chapter 1: The MVC Method

Getting Acquainted with MVC

Comparing MVC to Other Web Models

Seeing How MVC Fits into N-Tier Theory

Implementing MVC

Chapter 2: Selecting a Framework

Getting to Know PHP Frameworks

Knowing Why You Should Use a Framework

Focusing on Popular PHP Frameworks

Looking At Micro-Frameworks

Chapter 3: Creating an Application Using Frameworks

Building the Template

Creating an Application Scaffold

Modifying the Application Scaffold

Index

About the Author

Connect with Dummies

End User License Agreement

List of Tables

Book 1 Chapter 1

TABLE 1-1 HTML Versions

TABLE 1-2 HTTP Client Requests

TABLE 1-3 Common HTTP Server Response Status Codes

Book 1 Chapter 2

TABLE 2-1 Apache Web Server Error Levels

Book 2 Chapter 1

TABLE 1-1 HTML5 Section Elements

TABLE 1-2 HTML5 Text-Level Elements

TABLE 1-3 Ordered List Types

Book 2 Chapter 2

TABLE 2-1 CSS3 Pseudo-Elements

TABLE 2-2 The CSS3 Pseudo-Classes

TABLE 2-3 The CSS3 Cascading Rules Process

TABLE 2-4 CSS Font-Size Absolute Units of Measurement

TABLE 2-5 CSS Font-Size Relative Units of Measurement

Book 2 Chapter 3

TABLE 3-1 The Form Element Attributes

TABLE 3-2 HTML5 Form Field Elements

TABLE 3-3 The textarea Attributes

Book 2 Chapter 4

TABLE 4-1 The CSS3 Border Image Properties

TABLE 4-2 Font File Formats

TABLE 4-3 The CSS2 @media Types

TABLE 4-4 The CSS3 Media Features

Book 2 Chapter 5

TABLE 5-1 The CSS3 2D Transform Effects

TABLE 5-2 Defining the Area Element Hotspots

TABLE 5-3 Audio File and MIME Types

TABLE 5-4 The

<audio>

Tag Attributes

TABLE 5-5 Common Video Formats

TABLE 5-6 The

<video>

Tag Attributes

Book 3 Chapter 1

TABLE 1-1 JavaScript Math Operators

TABLE 1-2 JavaScript Boolean Operators

TABLE 1-3 The JavaScript Comparison Operators

TABLE 1-4 JavaScript Looping Statements

Book 3 Chapter 2

TABLE 2-1 JavaScript Document Properties

TABLE 2-2 JavaScript Document Methods

TABLE 2-3 JavaScript DOM Object Properties

TABLE 2-4 JavaScript DOM Object Methods

TABLE 2-5 The DOM Text Box Properties

TABLE 2-6 The DOM Check Box Properties

Book 3 Chapter 3

TABLE 3-1 The jQuery Class Functions

TABLE 3-2 The jQuery Functions to Add DOM Nodes

Book 3 Chapter 4

TABLE 4-1 Mouse Events

TABLE 4-2 Page Events

TABLE 4-3 The jQuery Event Functions

Book 3 Chapter 5

TABLE 5-1 Debugger Control Icons

TABLE 5-2 JavaScript Error Types

Book 4 Chapter 1

TABLE 1-1 PHP Arithmetic Operators

TABLE 1-2 PHP Boolean Operators

Book 4 Chapter 2

TABLE 2-1 PHP Comparison Operators

Book 4 Chapter 3

TABLE 3-1 PHP Extension Categories

TABLE 3-2 PHP String Manipulation Functions

TABLE 3-3 PHP String Splitting Functions

TABLE 3-4 PHP String Testing Functions

TABLE 3-5 PHP Arithmetic Functions

TABLE 3-6 PHP Logarithmic and Exponential Functions

TABLE 3-7 PHP Trigonometric Functions

TABLE 3-8 PHP Hyperbolic Functions

TABLE 3-9 The PHP

date()

Function Format Codes

TABLE 3-10 The GD2 Library Drawing Functions

Book 4 Chapter 4

TABLE 4-1 htmlspecialchars Flags

TABLE 4-2 The filter_var Data Sanitizing Options

TABLE 4-3 The filter_var() Data Validation Options

Book 4 Chapter 6

TABLE 6-1 Types of HTTP Cookies

TABLE 6-2 HTTP Cookie Attributes

Book 5 Chapter 1

TABLE 1-1 Standard Database Data Types

TABLE 1-2 SQL Commands

TABLE 1-3 SQL Query Modifiers

TABLE 1-4 The MySQL Storage Engines

Book 5 Chapter 2

TABLE 2-1 MySQL Command-Line Tools

TABLE 2-2 The mysql Commands

TABLE 2-3 MySQL Privileges

Book 5 Chapter 3

TABLE 3-1 ALTER TABLE Actions

Book 5 Chapter 4

TABLE 4-1 The phpMyAdmin Export Formats

Book 5 Chapter 5

TABLE 5-1 PHP Database Extension Libraries

TABLE 5-2 The mysqli Data Retrieval Functions and Methods

TABLE 5-3 Additional mysqli Library Functions

Book 6 Chapter 1

TABLE 1-1 The Bidders Table Layout

TABLE 1-2 The Items Table Layout

TABLE 1-3 The Admins Table Layout

Book 6 Chapter 3

TABLE 3-1 The XMLHttpRequest Class Methods

TABLE 3-2 The XMLHttpRequest Class Properties

TABLE 3-3 The $.ajax() Function Settings

TABLE 3-4 Popular PHP DOMDocument Methods

Book 6 Chapter 4

TABLE 4-1 The WordPress API Library Categories

List of Illustrations

Book 1 Chapter 1

FIGURE 1-1: Program code embedded in a web page.

FIGURE 1-2: Using client-side code in a web page.

FIGURE 1-3: Using server-side programming to create a web page.

FIGURE 1-4: Combining client-side and server-side programming.

Book 1 Chapter 2

FIGURE 2-1: The main phpMyAdmin page showing everything that is running.

FIGURE 2-2: The XAMPP Select Components window in the installation wizard.

FIGURE 2-3: The main XAMPP Control Panel window.

FIGURE 2-4: The

phpinfo()

function output.

Book 2 Chapter 1

FIGURE 1-1: The output for the sample web page.

FIGURE 1-2: A basic web page layout using HTML5 section elements.

FIGURE 1-3: Displaying all six heading levels in the Chrome web browser.

FIGURE 1-4: Using the hr element in a web page.

FIGURE 1-5: Displaying hypertext in a document.

FIGURE 1-6: Displaying an unordered list.

FIGURE 1-7: The display default for an ordered list.

FIGURE 1-8: Displaying a description list.

FIGURE 1-9: Displaying the table in Chrome.

FIGURE 1-10: Using the

rowspan

attribute in a table.

FIGURE 1-11: Using the

colspan

attribute in a table.

Book 2 Chapter 2

FIGURE 2-1: Using the first-letter pseudo-element on text.

FIGURE 2-2: Displaying elements with different colors in CSS3.

FIGURE 2-3: The CSS3 box model.

FIGURE 2-4: The updated

colortest.html

file output.

FIGURE 2-5: Adding a border to the table.

FIGURE 2-6: Displaying the web page with no positioning.

FIGURE 2-7: Using absolute positioning to place sections in the web page.

FIGURE 2-8: Using float positioning to place sections in the web page.

Book 2 Chapter 3

FIGURE 3-1: Using a fieldset to group form fields.

FIGURE 3-2: Using check boxes in a fieldset.

FIGURE 3-3: Using radio buttons to make a selection from a group.

FIGURE 3-4: The file input type interface as shown in the Microsoft Edge browse...

FIGURE 3-5: Using the

select

element.

FIGURE 3-6: Displaying multiple options in the select element.

FIGURE 3-7: Using a data list in the web page.

FIGURE 3-8: Viewing the

inputtypestest.html

output in the Google Chrome browser...

FIGURE 3-9: Using the placeholder HTML5 attribute.

Book 2 Chapter 4

FIGURE 4-1: Using the

border-radius

property to create rounded corners.

FIGURE 4-2: Slicing a border image to retrieve the pieces.

FIGURE 4-3: Using a Mozilla border image around an element.

FIGURE 4-4: A left-to-right color gradient.

FIGURE 4-5: Adding the text shadow effect to a heading element.

FIGURE 4-6: Using a box shadow on a div element.

Book 2 Chapter 5

FIGURE 5-1: Rotating images on the web page.

FIGURE 5-2: The audio controls in the Microsoft Edge browser.

FIGURE 5-3: Playing a video in the Microsoft Edge browser.

Book 3 Chapter 1

FIGURE 1-1: Testing the

scriptheadtest.html

program file.

FIGURE 1-2: Running JavaScript code in the body section.

FIGURE 1-3: The JavaScript

prompt()

function as displayed by the Microsoft Edge...

FIGURE 1-4: The JavaScript

alert()

function response as displayed by the Micros...

FIGURE 1-5: Prompting for the factorial number.

FIGURE 1-6: Displaying the factorial result.

Book 3 Chapter 2

FIGURE 2-1: The html object and its two contained elements.

FIGURE 2-2: The simple DOM tree.

FIGURE 2-3: The output from the domtest.html program.

FIGURE 2-4: The initial page and dialog box for the

findtest.html

web page.

FIGURE 2-5: The

walkingtest.html

results.

Book 3 Chapter 3

FIGURE 3-1: The output from the

jquery1.html

program.

FIGURE 3-2: The result of the

jquery2.html

program.

FIGURE 3-3: Changing the element using the

.html()

function.

FIGURE 3-4: The result of the

jquery4.html

program.

Book 3 Chapter 4

FIGURE 4-1: Running a function when the web page loads in the Chrome browser.

FIGURE 4-2: The Help alert dialog box appearing from the

buttontest.html

applic...

FIGURE 4-3: Counting keystrokes in the

keytest.html

program.

FIGURE 4-4: The jhover.html code test only changes one p element at a time.

FIGURE 4-5: The output of the jkeytest.html program in action.

Book 3 Chapter 5

FIGURE 5-1: The Microsoft Edge Developer Tools interface.

FIGURE 5-2: Using the DOM Explorer to examine the HTML in a web page.

FIGURE 5-3: The Developer Tools Console window in Microsoft Edge.

FIGURE 5-4: The Source debugger interface in the Microsoft Edge Developer Tools...

FIGURE 5-5: Pausing the code at a breakpoint in the Debugger.

FIGURE 5-6: Stopping the Debugger later in the code.

FIGURE 5-7: Catching an invalid data entry using the

try-catch

statement.

Book 4 Chapter 1

FIGURE 1-1: Processing PHP code in a web page.

FIGURE 1-2: Output generated by the

phptest.php

program.

FIGURE 1-3: Viewing the HTML5 code generated by the

phptest.php

program.

FIGURE 1-4: Output from the

phpdatatest.php

program.

FIGURE 1-5: The results of the

mymain.php

program.

FIGURE 1-6: The output from the

mybadmain.php

program.

Book 4 Chapter 2

FIGURE 2-1: The output from the

phpconditiontest.php

program.

FIGURE 2-2: The output of the

phpwhiletest.php

program.

FIGURE 2-3: The output from the

foreachtest.php

program.

FIGURE 2-4: The output from the

factest.php

program.

FIGURE 2-5: The output from the

linktest.html

file.

FIGURE 2-6: The result of clicking the “buy a product” link on the linktest.htm...

FIGURE 2-7: The web form produced by the

formtest.html

file.

FIGURE 2-8: The form results as shown from the

formtest.php

file.

Book 4 Chapter 3

FIGURE 3-1: The output from the

phpinfo()

function.

FIGURE 3-2: The web page generated by the

parseinput.html

code.

FIGURE 3-3: The web page result from the

parseoutput.php

code.

FIGURE 3-4: The output from the

imageupload.html

program.

FIGURE 3-5: Displaying the resampled and resized image.

Book 4 Chapter 4

FIGURE 4-1: The output from entering embedded JavaScript in a form.

FIGURE 4-2: The output from adding the

htmlspecialchars()

function.

FIGURE 4-3: The output from adding the

filter_var()

function.

FIGURE 4-4: The result from entering an invalid age value into the

typetest.htm

...

FIGURE 4-5: The result from entering an invalid email address.

Book 4 Chapter 5

FIGURE 5-1: The output from the

ooptest1.php

program.

FIGURE 5-2: The output from the

ooptest2.php

program.

FIGURE 5-3: The output from the

ooptest3.php

program.

FIGURE 5-4: The output from the

ooptest4.php

program.

Book 4 Chapter 6

FIGURE 6-1: Displaying the cookie in the Microsoft Edge Developer Tools window.

FIGURE 6-2: The result of the

cookietest2.php

code displaying the cookie data.

FIGURE 6-3: Looking for the PHP session cookie using the Developer Tools.

FIGURE 6-4: The output from the

sessiontest2.php

file.

FIGURE 6-5: The error message generated from trying to access data in an expire...

FIGURE 6-6: The initial shopping cart web page.

FIGURE 6-7: The shopping cart after selecting products.

Book 5 Chapter 1

FIGURE 1-1: A simple database management system.

FIGURE 1-2: A shared Microsoft Access environment.

FIGURE 1-3: A multiuser MySQL environment.

FIGURE 1-4: An example of an Employees table layout.

FIGURE 1-5: A view of customer order information.

Book 5 Chapter 2

FIGURE 2-1: The status command output.

FIGURE 2-2: The MySQL Workbench download web page.

FIGURE 2-3: The main Workbench window.

FIGURE 2-4: The Workbench Setup New Connection dialog box.

FIGURE 2-5: The Workbench administration window.

FIGURE 2-6: Submitting a query using MySQL Workbench.

FIGURE 2-7: The main phpMyAdmin window.

FIGURE 2-8: The MySQL Workbench Users and Privileges window.

FIGURE 2-9: Creating a new user account using Workbench.

FIGURE 2-10: The User Accounts Overview window in phpMyAdmin.

FIGURE 2-11: Entering a new user account in phpMyAdmin.

FIGURE 2-12: Displaying global user privileges from the CLI.

FIGURE 2-13: The Workbench Users and Privileges window.

FIGURE 2-14: The Workbench form to add schema privileges.

FIGURE 2-15: Adding schema privileges using Workbench.

FIGURE 2-16: Using the phpMyAdmin tool to display user accounts.

FIGURE 2-17: Setting database privileges using the phpMyAdmin tool.

Book 5 Chapter 3

FIGURE 3-1: Creating a new database using Workbench.

FIGURE 3-2: The Workbench Create Database Wizard.

FIGURE 3-3: The results of the Workbench Create Database Wizard.

FIGURE 3-4: The phpMyAdmin Databases page.

FIGURE 3-5: The phpMyAdmin database web page.

FIGURE 3-6: The phpMyAdmin database operations web page.

FIGURE 3-7: Creating a new table using Workbench.

FIGURE 3-8: The completed New Table form for the Employees table.

FIGURE 3-9: The

CREATE TABLE

statement generated by Workbench.

FIGURE 3-10: Viewing the Employees table created in the

dbtest2

database.

FIGURE 3-11: The database structure page in phpMyAdmin.

FIGURE 3-12: The empty new table form in phpMyAdmin.

FIGURE 3-13: The Index dialog box in phpMyAdmin.

FIGURE 3-14: The completed new table form in phpMyAdmin.

FIGURE 3-15: The phpMyAdmin table structure page.

FIGURE 3-16: The phpMyAdmin database structure page with an existing table.

Book 5 Chapter 4

FIGURE 4-1: The Workbench Result Grid for displaying table data.

FIGURE 4-2: The Apply SQL Wizard in Workbench.

FIGURE 4-3: Using the Form Editor in Workbench to manage data records.

FIGURE 4-4: The phpMyAdmin Database web page.

FIGURE 4-5: The

INSERT

form in phpMyAdmin.

FIGURE 4-6: The phpMyAdmin window for browsing data records.

FIGURE 4-7: The output from the

mysqldump

utility.

FIGURE 4-8: The Workbench Data Export window.

FIGURE 4-9: The Workbench Data Export advanced options window.

FIGURE 4-10: The phpMyAdmin export web page.

FIGURE 4-11: The Workbench Data Import/Restore window.

FIGURE 4-12: The phpMyAdmin Import web page.

Book 5 Chapter 5

FIGURE 5-1: The output from the

phpapptest.php

program.

Book 6 Chapter 1

FIGURE 1-1: Sample rule-of-thirds layout.

FIGURE 1-2: The basic AuctionHelper web page layout.

FIGURE 1-3: The AuctionHelper login window.

FIGURE 1-4: The main AuctionHelper window.

Book 6 Chapter 2

FIGURE 2-1: The main AuctionHelper web page.

FIGURE 2-2: The web page generated by the

listbidders.inc.php

include file.

FIGURE 2-3: The web page generated by the

displaybidder.inc.php

include file.

FIGURE 2-4: The web page generated by the

updatebidder.inc.php

include file.

FIGURE 2-5: The web page generated by the

newbidder.inc.php

include file.

FIGURE 2-6: The web page generated by the

listitems.inc.php

include file.

FIGURE 2-7: The web page generated by the

updateitem.inc.php

include file.

FIGURE 2-8: The web page generated by the

newitem.inc.php

include file.

FIGURE 2-9: Process diagram for the AuctionHelper include files.

Book 6 Chapter 3

FIGURE 3-1: The basics of AJAX.

FIGURE 3-2: The

ajaxcars1.html

initial web page.

FIGURE 3-3: Viewing the XML output using the Microsoft Edge browser.

FIGURE 3-4: The output of the

xmltest.html

program.

FIGURE 3-5: The AuctionHelper main window.

FIGURE 3-6: Displaying the output from the

realtime.php

file.

FIGURE 3-7: The AuctionHelper main page with the real-time data added.

Book 6 Chapter 4

FIGURE 4-1: The WordPress Setup Configuration File web page.

FIGURE 4-2: The WordPress Installation web page.

FIGURE 4-3: The main WordPress web page for your website.

FIGURE 4-4: The WordPress Dashboard web page.

FIGURE 4-5: The WordPress Themes web page.

FIGURE 4-6: The Blog Articles theme as the active theme.

FIGURE 4-7: The First Street Elementary web page using the Blog Articles theme.

FIGURE 4-8: Activating the AuctionHelper plugin in WordPress.

FIGURE 4-9: The Widgets web page, showing the sidebar elements.

FIGURE 4-10: The AuctionHelper Widget item.

FIGURE 4-11: The result of adding the AuctionHelper widget to the WordPress web...

Book 7 Chapter 1

FIGURE 1-1: A basic MVC theory diagram.

FIGURE 1-2: The relational data method model.

FIGURE 1-3: The object-oriented data method model.

FIGURE 1-4: Using multiple view modules for different display environments.

FIGURE 1-5: The model–view–presenter method.

FIGURE 1-6: The model–view–viewmodel method.

FIGURE 1-7: The

n

-tier theory architecture.

Book 7 Chapter 2

FIGURE 2-1: Using a file-naming convention to handle web requests.

FIGURE 2-2: A CRUD interface generated by the CakePHP framework package.

FIGURE 2-3: Using routing to direct client requests.

FIGURE 2-4: The default CakePHP framework web page.

FIGURE 2-5: The default CodeIgniter framework web page.

FIGURE 2-6: The default Laravel framework web page.

FIGURE 2-7: The default Symfony framework web page.

FIGURE 2-8: The default Laminas MVC Framework web page.

FIGURE 2-9: The default Slim framework web page.

Book 7 Chapter 3

FIGURE 3-1: The generic CakePHP application web page.

FIGURE 3-2: The main Bidders scaffolding web page.

FIGURE 3-3: The new link in the bidders action links.

FIGURE 3-4: The CakePHP error message generated by clicking the new link.

FIGURE 3-5: The find error message from the application.

FIGURE 3-6: The missing template error message.

FIGURE 3-7: The final results of adding the items won feature to the scaffoldin...

Guide

Cover

Table of Contents

Title Page

Copyright

Begin Reading

Index

About the Author

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PHP, MySQL®, & JavaScript® All-in-One For Dummies®, 2nd Edition

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Library of Congress Control Number: 2025938536

ISBN 978-1-394-34209-9 (pbk); ISBN 978-1-394-34211-2 (ebk); ISBN 978-1-394-34210-5 (ebk)

Introduction

The Internet has become an amazing place to shop, do your banking, look up homework assignments, and even keep track of your bowling league scores. Behind all those great applications are a bunch of different web technologies that must all work together to create the web experience you come to expect.

You may think that creating web applications is best left for the professionals, but you’d be surprised by just how well you can do with just a little knowledge and experience! That’s the point of this book.

About This Book

Think of this book as a reference book. Like the dictionary or an encyclopedia (remember those?), you don’t have to read it from beginning to end. Instead, you can dip into the book to find the information you need and return to it again when you need more. That said, you won’t be disappointed if you work through the book from beginning to end, and you may find it easier to follow along with some of the examples.

In this book, I walk you through all the different technologies involved with creating dynamic web applications that can track data and present it in an orderly and pleasing manner. I cover several key topics that you’ll need to know to create a full-featured, dynamic web application:

Creating the basic layout of a web page:

In this book, you see the program code behind placing content on a web page and reacting to your website visitors’ mouse clicks.

Styling the web page:

Just placing data on a web page is boring. In this book, you learn how to use CSS to help use color, images, and placement to help liven up your web applications.

Adding dynamic features:

These days, having a static web page that just sits there doesn’t get you many followers. This book shows you how to incorporate JavaScript to animate your web pages and provide dynamic features.

Leveraging the power of the server:

The PHP programming language allows you to harness the power behind the web server to dynamically generate web pages “on the fly” as your website visitors make choices.

Storing data for the future:

Just about every dynamic web application needs to store data, and in this book you learn exactly how to do that using the MySQL server, which is commonly available in just about every web platform.

Creating full applications:

Many books throw a bunch of technology at you and expect you to put the pieces together yourself. This book not only shows you the technology, but also demonstrates how all the parts fit together to create a dynamic web application.

Using helper programs:

No one is an island; everyone needs some help putting together those fancy web applications. There are plenty of tools to help you get the job done, and with this book you find out which tools will help you with which features of your application.

Throughout this book you see sidebars (text in gray boxes) and material marked with the Technical Stuff icon. All of these things are skippable. If you have time and are interested, by all means read them, but if you don’t or aren’t, don’t.

Finally, within this book, you may note that some web addresses break across two lines of text. If you’re reading this book in print and want to visit one of these web pages, simply key in the web address exactly as it’s noted in the text, pretending as though the line break doesn’t exist. If you’re reading this as an e-book, you’ve got it easy — just click the web address to be taken directly to the web page.

Foolish Assumptions

You don’t need any level of programming experience to enjoy this book and start creating your own web applications. Each chapter walks through all the basics you need to know and doesn’t assume you’ve ever coded before. As long as you’re reasonably comfortable navigating your way around a standard desktop computer, you have all the experience you need!

That said, if you’ve already tried your hand at web programming and you just want to fill in a few holes, this book will work well for you, too!

This book doesn’t expect you to run out and buy any expensive software packages to start your web development career. All the tools that are used in the book are freely available open-source software. I walk you through how to set up a complete development environment, whether you’re working in Microsoft Windows, Apple macOS, or Linux.

Icons Used in This Book

I use some icons throughout the book to help you identify useful information. Here are the icons and what I use them for:

Anything marked with the Tip icon provides some additional information about a topic to help you better understand what’s going on behind the scenes or how to better use the feature discussed in the text.

You don’t have to commit this book to memory — there won’t be a test. But every once in a while, I tell you something so important that you should remember it. When I do, I mark it with the Remember icon.

The Warning icon is there to point out potential pitfalls that can cause problems. If you want to save yourself a lot of time or trouble, heed these warnings.

This icon explains technical details about the concept being explained. The details might be informative or interesting, but are not essential to your understanding of the concept at this stage.

Beyond the Book

So that you don't have to spend your precious time typing in long blocks of code, I have provided much of the code you find in this book for you online. You can download this code for each book and chapter by going to www.dummies.com/go/phpmysqlandjavascriptaio2e and following the instructions there.

You also get access to a free online Cheat Sheet filled with more tips and tricks on building a web application, including accessing any database from your PHP programs, filtering data your program receives from web forms to block unwanted or potentially dangerous data, quickly finding data in a MySQL database, and triggering JavaScript events at predetermined times in a browser. To access this resource go to www.dummies.com and enter PHP, MySQL & JavaScript All-in-One For Dummies Cheat Sheet in the search box.

Where to Go from Here

This book doesn’t have to be read from beginning to end, so you can dive in wherever you want! Use the Table of Contents and Index to find subjects that interest you. If you already know PHP and JavaScript and you’re just interested in learning how to create a dynamic web application from scratch, start out with Book 6, Chapter 1. If you’re interested in learning how to use one of the framework packages available for PHP, check out Book 7, Chapter 1. Or, if you’re interested in everything, start with Book 1, Chapter 1, and read until the very end.

With the information in this book, you’ll be ready to start creating your own dynamic web applications. Web programming is one of those skills that takes time and practice to get good at, so the more coding you can do, the better you’ll get at it. To get some practice, you may want to offer your services for free at first, to build up a reputation. Find a needy nonprofit organization that you’re interested in supporting and offer to work on its website. They’ll get a great website, and you’ll get a project to add to your résumé!

Don’t stop learning! There are always new things coming out in the web world, even if you just stick to using the same software packages to develop your web applications. Stay plugged in to the PHP world by visiting the official PHP website at www.php.net or by visiting (and even participating in) one or more of the many PHP forums. Just do some Googling to find them.

Enjoy your newfound skills in developing dynamic web applications!

Book 1

Getting Started with Web Programming

Contents at a Glance

Chapter 1: Examining the Pieces of Web Programming

Creating a Simple Web Page

Creating a Dynamic Web Page

Storing Content

Chapter 2: Using a Web Server

Recognizing What’s Required

Considering Your Server Options

Tweaking the Servers

Building a Development Environment

Chapter 1

Examining the Pieces of Web Programming

IN THIS CHAPTER

Understanding how simple web pages work

Incorporating programming into your web page

Storing content in a database

At first, diving into web programming can be somewhat overwhelming. You need to know all kinds of things in order to build a web application that not only looks enticing but also works correctly. The trick to learning web programming is to pull the individual pieces apart and tackle them one at a time.

This chapter gets you started on your web design journey by examining the different pieces involved in creating a simple web page. Then it kicks things up a notch and walks you through dynamic web pages. And finally, the chapter ends by explaining how to store your content for use on the web.

Creating a Simple Web Page

Before you can run a marathon, you need to learn how to walk. Likewise, before you can create a fancy website, you need to know the basics of how web pages work.

Nowadays, sharing documents on the Internet is easy, but it wasn’t always that way. Back in the early days of the Internet, documents were often created using proprietary word-processing packages and had to be downloaded using the cumbersome File Transfer Protocol (FTP). To retrieve a document, you had to know exactly what server contained the document, you had to know where it was stored on the server, and you had to be able to log into the server. After all that, you still needed to have the correct word-processing software on your computer to view the document. As you can imagine, it wasn’t long before a new way of sharing content was required.

To get to where we are today, several different technologies had to be developed:

A method for linking related documents together

A way for the document reader to display formatted text the same way in any type of device

An Internet standard allowing clients to easily retrieve documents from any server

A standard method of styling and positioning content in documents

This section describes the technology that made viewing documents on the Internet work the way it does today.

Kicking things off with the World Wide Web

In 1989, Tim Berners-Lee developed a method of interconnecting documents to make sharing research information on the Internet easier. His creation, the World Wide Web, defined a method for linking documents together in a web structure, so that a researcher could follow the path between related documents, no matter where they were located in the world. Clicking text in one document took you to another document automatically, without your having to manually find and download the related document.

The method Berners-Lee developed for linking documents is called hypertext. Hypertext embeds links that are hidden from view in the document and directs the software being used to view the document (known as the web browser) to retrieve the referenced document. With hypertext, you just click the link, and the software (the web browser) does all the work of finding and retrieving the related document for you.

Because the document-viewing software does all the hard work, a new type of software had to be developed that was more than just a document viewer. That’s where web browsers came into existence. Web browsers display a document on a computer screen and respond to the reader clicking hypertext links to retrieve other specified documents.

To implement hypertext in documents, Berners-Lee had to utilize a text-based document-formatting system. Fortunately for him, a lot of work had already been done on that.

Making sense of markup languages

Markup languages were developed to replace proprietary word-processing packages with a standard way of formatting documents so that they could be read by any type of document viewer on any type of device. This goal is accomplished by embedding tags in the text. Each tag indicates a formatting feature, such as headings, bold or italic text, or special margins. What made markup languages different from word-processing packages is that these tags were common text codes instead of proprietary codes, making it generic enough that any device could read and process them.

The first popular markup language was the Generalized Markup Language (GML), developed by IBM in the 1960s. The International Organization for Standardization (ISO) took up the challenge of creating markup languages and produced the Standard Generalized Markup Language (SGML), mainly based on GML, in the 1980s. However, because SGML was developed to cover all types of document formatting on all types of devices, it’s extremely complex and it wasn’t readily adapted.

Berners-Lee used the ideas developed in SGML to create a simplified markup language that could support his hypertext idea. He called it Hypertext Markup Language (HTML). HTML uses the same concept of tags that SGML uses, but it defines fewer of them, making it easier to implement in software.

An example of an HTML tag is <h1>. You use this tag to define text that's used as a page heading. Just surround the text with an opening <h1> tag, and a corresponding closing </h1> tag, like this:

<h1>This is my heading</h1>

When the browser gets to the <h1> tag, it knows to format the text embedded in the opening and closing tags using a different style of formatting, such as a larger font or a bold typeface.

To define a hypertext link to another document, you use the <a> tag:

<a href="anotherdoc.html">Click here for more info</a>

When the reader clicks the Click here for more info text, the browser automatically tries to retrieve the document specified in the <a> tag. That document can be on the same server or on another server anywhere on the Internet.

HTML development has seen quite a few changes since Berners-Lee created it and turned it over to the World Wide Web Consortium (W3C) to maintain. After many years of faithfully maintaining the HTML standard, unfortunately, it had met with some controversy, as a competing standard, maintained by the Web Hypertext Application Technology Working Group (WHATWG), a consortium of several vendors, emerged. Table 1-1 shows the path the HTML standard has taken.

TABLE 1-1 HTML Versions

Version

Description

HTML 1.0

Formally released in 1989 as the first public version of HTML

HTML 2.0

Released in 1995 to add interactive elements

HTML 3.0

Released in 1996 but never widely adopted

HTML 3.2

Released in 1997, adding support for tables

HTML 4.01

Released in 1999, widely adopted, and remains an often-used standard

XHTML 1.0

Released in 2001, standardizing HTML around the XML document format

XHTML 1.1

Released in 2002, making updates and corrections to XHTML 1.1

HTML 5.0

Released in 2014, adding multimedia features

HTML 5.1

Released in mid-2017, adding form validation and context menus

HTML 5.2

Released in late-2017, adding additional styling features

HTML 5.3

Also released in late-2017, this was the final version released by the W3C

In 2019, the W3C stopped as the sole maintainer of the official HTML standard and joined with the WHATWG consortium to produce a single HTML standard, called the HTML Living Standard. This is now considered the official HTML standard, and the standard that this book focuses on. The Living Standard doesn’t have specific release versions, but instead, incorporates changes “on the fly” to the HTML specifications once they are approved by their board. You can find the latest HTML features described at the WHATWG website, html.spec.whatwg.org/multipage/. The WHATWG documentation refers to the term HTML5 as a buzzword, often used to describe the modern HTML standard.

Retrieving HTML documents

Besides a document-formatting standard, Berners-Lee also developed a method of easily retrieving the HTML documents in a client–server environment. A web server software package runs in the background on a server, listening for connection requests from web clients (the browser). The browser sends requests to retrieve HTML documents from the server. The request can be sent anonymously (without using a login username), or the browser can send a username and password or certificate to identify the requestor.

These requests and responses are defined in the Hypertext Transfer Protocol (HTTP) standard. HTTP defines a set of requests the client can send to the server and a set of responses the server uses to reply back to the client.

This section walks you through the basics of how web servers and web clients use HTTP to interact with each other to move web pages across the Internet.

Web clients

The web client sends requests to the web server on a standard network communication channel. The requests use a common Internet protocol known as Transmission Control Protocol (TCP). Each TCP connection uses a defined port number to communicate between the server application and clients. HTTP uses TCP port 80 as the standard for communications between servers and clients. HTTP uses standard text requests sent to the server, either requesting information from the server or sending information to the server. Table 1-2 shows the basic HTTP client requests available.

TABLE 1-2 HTTP Client Requests

Request

Description

CONNECT

Converts the connection into a secure tunnel for sending data

DELETE

Deletes the specified resource

GET

Requests the specified resource

HEAD

Requests the title of the specified resource

OPTIONS

Retrieves the HTTP requests that the server supports

PATCH

Applies a modification to a resource

POST

Sends specified data to the server for processing

PUT

Stores specified data at a specified location

TRACE

Sends the received request back to the client

As shown in Table 1-2, when you ask to view a web page from your client browser, the browser sends the HTTP GET request to the server, specifying the filename of the web page. The server then responds with a response code along with the requested data. If the client doesn't specify a filename in the GET request, most servers have a default file with which to respond.

Web servers

With HTTP, the web server must respond to each client request received. If the client sends a request that the server can’t process, the server must send some type of error code back to the client indicating that something went wrong.

The first part of the server response is a status code and text that the client uses to determine whether the submitted request was successful. The format of the HTTP response uses a three-digit status code, followed by an optional text message that the browser can display. The three-digit codes are broken down into five categories:

1xx:

Informational messages

2xx:

Success

3xx:

Redirection

4xx:

Client error

5xx:

Server error

The three-digit status code is crucial to knowing what happened with the response. Many status codes are defined in the HTTP standards, providing some basic information on the status of client requests. Table 1-3 shows just a few of the standard HTTP response codes that you may run into.

As you can see from Table 1-3, a web server can return many possible responses. It’s the client’s job to parse the response and determine the next action to take.

If the response indicates the request was successful, the server will follow the response code with the data related to the request, such as the contents of an HTML file. The client must then read the returned data and decide what to do with it. For HTML files, the browser will display the requested file, applying the HTML formatting tags to the data.

Don’t worry about trying to memorize all the HTTP status codes. Most of them you’ll never run into in your web-programming career. Before long, you’ll start to remember a few of the more common ones, and you can always look up any others you run into.

TABLE 1-3 Common HTTP Server Response Status Codes

Status Code

Text Message

Description

100

Continue

The client should send additional information.

101

Switching Protocols

The server is using a different protocol for the request.

102

Processing

The server is working on the response.

200

OK

The server accepted the request and has returned the response.

201

Created

The server created a new resource in response to the request.

202

Accepted

The data sent by the client has been accepted by the server but has not completed processing the data.

206

Partial Content

The response returned by the server is only part of the full data; more will come in another response.

300

Multiple Choices

The request matched multiple possible responses from the server.

301

Moved Permanently

The requested file was moved and is no longer at the requested location.

302

Found

The requested resource was found at a different location.

303

See Other

The requested resource is available at a different location.

304

Not Modified

The requested resource was not modified since the last time the client accessed it.

307

Temporary Redirect

The requested resource was temporarily moved to a different location.

308

Permanent Redirect

The requested resource was permanently moved to a different location.

400

Bad Request

The server cannot process the request.

401

Unauthorized

The resource requires authentication that the client did not provide.

402

Payment Required

The requested resource is not freely available.

403

Forbidden

The resource requires authentication, and the client does not have the proper permission.

404

Not Found

The requested resource was not located on the server.

414

URI Too Long

The Uniform Resource Identifier (URI) describing the location of the resource was longer than the server is able to handle.

415

Unsupported Media Type

The server does not know how to process the requested resource file.

429

Too Many Requests

The client has sent too many requests within a specific amount of time.

500

Internal Server Error

An unexpected condition occurred on the server while trying to retrieve the requested resource.

501

Not Implemented

The server doesn’t recognize the request.

502

Bad Gateway

The server was acting as a proxy to another server but received an invalid response from the other server.

503

Service Unavailable

The server is currently unavailable, often due to maintenance.

505

HTTP Version Not Supported

The server doesn’t support the HTTP standard used by the client in the request.

507

Insufficient Storage

The server is unable to store the resource due to lack of storage space.

511

Network Authentication Required

The client is required to authenticate with a network resource to receive the response.

Styling your web content

The HTML standard defines how browsers perform basic formatting of text, but it doesn’t really provide a way to tell a browser how to display the text. The <h1> tag indicates that the text should be a heading, but nothing tells the browser just how to display the heading to make it different from any other text on the page.

This is where styling comes into play. Styling allows you to tell the browser just what fonts, sizes, and colors to use for text, as well as how to position the text in the display. This section explains how styling affects how your web pages appear to your visitors.

Style sheets

There are several ways to define styling for an HTML document. The most basic method is what the browser uses by default. When the browser sees an HTML formatting tag, such as the <h1> tag, it has a predefined font, size, and color that the developer of the browser felt was useful.

That's fine, but what if you want to make some headings black and others red? This is possible with inline styling. Inline styling allows you to define special styles that apply to only one specific tag in the document. For example, to make one heading red, you’d use the following HTML:

<h1 style="color: red">Warning, this is bad</h1>

The style term is called an attribute of the <h1> tag. There are a few different attributes you can apply directly to tags within HTML; each one modifies how the browser should handle the tag. The style attribute allows you to apply any type of styling to this specific <h1> tag in the document. In this example, I chose to change the color of the text.

Now, you're probably thinking that I’ve just opened another can of worms. What if you want to apply the red color to all the <h1> tags in your document? That’s a lot of extra code to write! Don’t worry, there’s a solution for that.

Instead of inserting styles inline, you can create a style definition that applies to the entire document. This method is known as internal styling. It defines a set of styles at the top of the HTML document that are applied to the entire document. Internal styling looks like this:

<style>h1 {color: red;}</style>