An Introduction to PHP: Learn PHP 8 to Create Dynamic Websites

Table of Contents....5

About the Author....16

About the Technical Reviewers....17

Acknowledgments....18

Introduction....19

Chapter 1: Introduction and Setting Up....23

How the Web Works....24

The Sample Project....26

The Tools....27

A Coding Editor....28

Web Server Setup....29

Using the Virtual Hosts Applications....32

Adding the Domain Name....33

Editing the httpd.conf File....35

Adding a Virtual Host....37

Fixing the php.ini File....40

Configuring PHP....43

Setting PHP Options....45

Some Useful Configuration Options....46

PHP Execution....46

File Uploads....46

Legacy Settings....46

Sessions....47

Error Reporting....47

Other Settings....48

Starting Up....49

The Project Configuration Files....49

Finishing Up....51

Chapter 2: Working with PHP....53

Before We Start....54

Grouping: Brackets and Friends....54

Data Types....55

How PHP Processes Files....56

Renaming the Files....57

PHP Scripts....58

Experimenting....59

Adding Dynamic Data to the Page....61

Displaying Data....64

Including Files....66

Preparing and Implementing Include....68

Headings and Titles....70

Including Variables in the Include Files....71

Setting the Title and Heading....73

The Navigation Block....73

The Links Array....75

Creating the List of Links....76

Displaying the Links....80

Highlighting the Current Page....81

Comments....84

Summary....86

Coming Up....87

Chapter 3: Email and Form Processing....88

Preparation....89

The Contact Form....89

The Plan of Attack....93

Reading the Form Data....94

Outlining the Plan....96

Reading the Form Data....97

Preparing the Data....98

Persisting Fields....99

Form Validation....101

JavaScript and HTML5 Validation....101

Planning for Validation....102

Required Fields....103

Checking an Email Address....105

Email Injection....106

Handling the Errors....110

Displaying the Errors....110

The Errors Paragraph....111

Printing Empty Arrays....112

Sending Email with the mail() Function....113

The Main Email Variables....114

The Email Headers....116

The Header Data....117

After Sending the Message....120

Alternative Parts....120

Writing the Conditional Blocks....123

Reorganizing the Code....125

Configuration....125

Moving the Code....126

Summary....127

Coming Up....129

Chapter 4: Uploading Data and Files....130

The Upload Form....130

The File Input....133

Settings....134

Preliminary Coding....135

The Data Variables....135

Processing POSTed Data and Preliminary Validation....137

Image Validation....139

The $_FILES Array....139

Using File Data....140

Checking an Image File....143

Keeping the File....146

The File Name....147

Lower Case....149

Replacing Spaces....149

Defining the Location....150

Moving the File....152

Creating Additional Copies....153

Resized Image Configuration....155

Generating the Resized Copies....156

Tidying Up....157

Clearing the Error Array....157

Clearing the Old Values....158

Summary....158

Coming Up....159

Chapter 5: Working with a Database....160

Something About Databases....162

Running SQL....165

MySQL and PHPMyAdmin....165

Browsing....167

The Setup Page....167

Creating the Database and User....169

Preparing the Images Table....172

Using the Database with PHP....174

Connection....175

Connection String....175

Creating a Connection....176

A Crash Course in Classes and Objects....177

Handling Connection Errors....179

exit or die....180

Adding Options....181

Error Reporting....182

Prepared Statements....182

Setting the PDO Options....183

Using the Alternative Script....184

Summary....184

Coming Up....185

Chapter 6: Adding Data to the Database....186

Connecting to the Database....187

SQL Injection....188

Prepared Statements....190

When to Worry About SQL Injection....192

Adding the Image Data to the Table....193

Line Breaks....195

Creating Line Break Functions....196

The Prepared SQL Statement....200

Executing with Data....202

Retrieving the New ID....203

Modifying the Name....204

Constructing the New Name....205

Zero-Padding a Number....205

Updating the Database....206

Keeping the File and Creating the Resized Copies....207

Refactoring the Code....208

The Function Outline....208

Scope....210

Writing the addImageData() Function....211

Writing the addImageFile() Function....214

Using the Code in the Future....217

Summary....217

Coming Up....218

Chapter 7: File Handling....219

Preparation....220

The ZIP File....221

The CSV File....222

Processing the Uploaded Zip File....223

Checking the Zip File....224

Unzipping the File....226

Reading Text Files....231

Removing the Header Row....234

Splitting CSV Data....235

Importing the Data....237

Checking the MIME Types....239

Checking the Images....241

Finishing Up....243

A Crash Course in HTTP(S)....244

Headers Already Sent....246

Redirecting to the Next Page....247

Starting Over....250

Summary....254

Coming Up....255

Chapter 8: The Image Gallery....256

Preparation....257

Fetching the Thumbnails....259

Fetching from the Database....259

Fetching a Gallery Page....261

Fetching the Rows....265

Generating the Gallery Images....267

Selecting the Page....271

The Navigation Block....277

Remembering the Page....282

Displaying a Larger Image....286

Fetching a Miscellaneous Single Image....286

Selecting a Random Row from the Database....291

Fetching a Selected Image....293

Displaying a Random Image on Other Pages....296

Summary....300

Coming Up....302

Chapter 9: Managing Data....303

The Image Pages....304

The Image List Page....309

Preparatory Code for the Image List....310

Something About HTML Tables....312

Generating the Table Data....316

The Image Editing Page....323

The Prepare Events....324

Fetching the Data to be Edited....327

Adjusting the Image Blocks....329

Adjusting the Buttons....330

Adjusting the Upload Form....331

Disabling Fields for Remove....332

Implementing Update and Delete....333

Deleting Data....334

Updating the Image Data....337

Updating the Text Data....337

Replacing the Image....340

Checking a Checkbox....343

Adding the Checkbox....344

Testing the Checkbox....347

Finishing Touches....351

Clearing the $id when Adding an Image....351

Fixing the Hidden Field....352

Restoring the Images....352

Summary....353

Coming Up....355

Chapter 10: Sessions and Logging In....356

Sessions....357

Session Settings....358

Starting a Session....360

Using Session Data....363

Managing Users....365

Encryption and Hashing....366

Password Hashing in PHP....368

The User Table....369

Adding a User....370

Method 1: Running the SQL Directly....371

Method 2: Adding a Password Using PHPMyAdmin....374

Method 3: Adding an Admin User with the Setup Page....375

Logging In....376

Processing Login....377

Successful Login....381

Switching Between Content....382

Showing the User’s Name....384

Logging Out....387

Restricting Access....388

Summary....391

Coming Up....392

Chapter 11: A Configuration System....394

The ini File Contents....394

Reading an ini File....397

Generating the Configuration Form....402

Generating the Config Table....404

Saving the Configuration....409

Reading the New Values....409

Writing the ini File....411

Using the Configuration Settings....413

Resizing Images....416

Adding Configuration to Administration....421

Summary....422

Coming Up....423

Chapter 12: A Content Management System....424

The Blog Pages....425

The Blog Table....427

Preparatory Blog Code....430

Adding a Single Blog Article....435

Uploading the Optional Image....443

Checking for an Optional Image....445

Keeping the Optional Image....447

Previewing the Image....454

Selecting an Existing Image....456

Selecting an Image from a Menu....457

Processing the Selected Image....462

Previewing the Selected Image....465

Selecting an Image from a Radio Group....467

Choosing Between Buttons and the Menu....472

Redirecting to the Blog List Page....473

Importing Blog Articles....474

Changes to the Insert Code....474

Starting the Import Code....476

Handling the Import File....476

Copying the Blog Import Files....479

Importing the Blog Data....481

Calling a Function with an Array of Parameters....487

Finishing the Import....489

Reading a Blog Article....490

Preliminary Code....491

Getting the Selected Article ID....493

Fetching the Article....495

Fixing the Article Line Breaks....498

Displaying the Blog Image....500

Managing the Blog Articles....504

Building the Article Table....509

Processing the Prepare Events....512

Displaying the Image....515

Finishing the Preparation....518

Updating an Article....521

Deleting an Article....524

The Visitor Blog List....526

Preparatory Code....528

Generating the Blog Article List....530

Summary....533

Appendix A: Adding Markdown to Your Blog Articles....537

The Markdown Language....538

Adding Markdown to the Database....539

Adding a Checkbox to the Form....540

Reading the Markdown Setting....541

Manipulating the Markdown Setting....542

Displaying the Markdown Article....547

Appendix B: Non-PHP Tricks....551

Toggle Background....551

Visible Passwords....552

Required Upload....555

Preview Image....556

Previewing a Referenced Image....556

The File Input....558

Light Box....560

Paging Page Number....561

The Hopping Kangaroo....562

Appendix C: PHP Versions....564

The array() and list() Language Constructs....564

The … Operator....566

mail() Function Additional Headers....567

Function Data Types....569

Named Parameters....570

Appendix D: Default Library Functions....572

Resizing Images....573

The resizeImage() Function....574

Interpreting the Resize Dimensions....575

Loading the Original Image....579

Getting Information About the Original Image....580

Loading the Image Data....583

Saving the Resized Image....585

Creating the Blank Copy and Copying the Original....588

Copying the Original into the Image Copy....589

Padding Adjustments for Distorted Copies....592

Image Shapes....594

Adjusting the Size and Origin....595

The Complete resizeImage Function (So Far…)....598

Options....599

Omitting the Destination Name....600

Using the Options Array....602

Setting a Background Color....604

Changing the Saved Image Type....605

Setting a Clear Padding Background....607

Trimming the Image Copy....609

Using Named Parameters (PHP 8)....610

Named Parameters in the resizeImage() Function....612

splitSize....615

unzip Function....616

Markdown to HTML....621

Anchors....622

Headings....623

Miscellaneous Functions....624

The MimeType() Function....624

The printr() Function....625

Index....627

Use PHP to enhance your web pages. This book shows you how PHP programming works, and how to write and organize PHP code.

The book starts with steps to download and install a setup for a sample website that will form the basis for upcoming chapters. You start by writing PHP code and learn how to mix it with HTML and manage the code. From there, you will learn about dynamic content, along with a deep dive into form processing and sending email. Saving uploaded data and uploading files is discussed next. You will learn how to configure your PHP project and develop a library. You will then learn how to create an image catalog and manage data on your web page. By the end of the book, you will understand how to work with cookies, sessions, and logging in, followed by an example of creating a simple blog that reiterates the concepts developed in the previous chapters.

After reading this book, you will be able to configure, create, and manage your dynamic website.

What Will You Learn

• Know the basics of programming with the PHP language
• Use PHP to generate dynamic web pages
• Work with SQL databases
• Work with forms to upload text data and binary files
• Use tips and tricks to write clean and maintainable code

Who This Book Is For

Web developers and students learning to develop and maintain PHP code on their website