Backend DevelopmentPHP TutorialA brief discussion on how to use PHP to access and operate DOM (1)_PHP TutorialA brief discussion on how to use PHP to access and operate DOM (1)_PHP Tutorial
The DOM tree defines the logical structure of documents and controls how you access and manipulate these documents. Using the DOM, developers can create XML or HTML documents, manipulate their results, and add, modify, and delete document elements and content. The DOM can be accessed from any programming language. This article uses the PHP 5 DOM extension, which is part of the PHP core, so there is no need to install other software besides PHP.
DOM tree nodes follow XML naming conventions, such as:
1. Document node--represents the DOMDocument interface
2. Element node--represents the DOMElement interface
3. Attribute node--represents the DOMAttr interface
4. Comment node--represents the DOMComment interface
5. Text node--represents the DOMText interface
Extracting elements
This section introduces how to extract elements and values from the DOM tree. This article uses Book.xml as an example to illustrate, and its content is shown in Listing 1.
List 1 Book.xml
<ol class="dp-xml"> <li class="alt"><span><strong><font color="#006699"><span class="tag"></span><span class="tag-" name>xml</span></font></strong><span> </span><span class="attribute"><font color="#ff0000">version</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">"1.0"</font></span><span> </span><span class="attribute"><font color="#ff0000">encoding</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">"UTF-8"</font></span><span> </span><span class="attribute"><font color="#ff0000">standalone</font></span><span>=</span><span class="attribute-value"><font color="#0000ff">"yes"</font></span><span> </span><span class="tag"><strong><font color="#006699">?></font></strong></span><span> </span></span></li> <li> <span></span><strong><font color="#006699"><span class="tag"><span class="tag-" name>book</span><span class="tag">></span></span></font></strong><span> </span> </li> <li class="alt"> <span></span><span class="comments"><font color="#008200"><!--XML Processing [part I] --></font></span><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>name</span><span class="tag">></span></span></font></strong><span>XML Processing I</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">name</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">author</span><span class="tag">></span></span></font></strong><span>John Smith Jr.</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">author</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">publisher</span><span class="tag">></span></span></font></strong><span>HisOwnTM</span><strong><font color="#006699"><span class="tag"></span><span class="tag-" name>publisher</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">ISBN</span><span class="tag">></span></span></font></strong><span>111-222-333-4441</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">ISBN</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">contents</span><span class="tag">></span></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>chapter_I</span><span class="tag">></span></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">title</span><span class="tag">></span></span></font></strong><span>What is XML about ?</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">title</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>content</span><span class="tag">></span></span></font></strong><span>XML (Extensible Markup Language) is a ...</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">content</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">chapter_I</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>chapter_II</span><span class="tag">></span></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">title</span><span class="tag">></span></span></font></strong><span>SAX</span><strong><font color="#006699"><span class="tag"></span><span class="tag-" name>title</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>content</span><span class="tag">></span></span></font></strong><span>SAX is a simple API for ...</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">content</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">chapter_II</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>chapter_III</span><span class="tag">></span></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">title</span><span class="tag">></span></span></font></strong><span>StAX</span><strong><font color="#006699"><span class="tag"></span><span class="tag-" name>title</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>content</span><span class="tag">></span></span></font></strong><span>Much powerful and flexible, StAX, is very...</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">content</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">chapter_III</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>chapter_IV</span><span class="tag">></span></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">title</span><span class="tag">></span></span></font></strong><span>DOM </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">subtitle</span><span class="tag">></span></span></font></strong><span>DOM concept </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">continut</span><span class="tag">></span></span></font></strong><span>Starting to use DOM...</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">continut</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag">subtitle</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">subchapter_IV_I</span><span class="tag">></span></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-name">title</span><span class="tag">></span></span></font></strong><span>First DOM application...</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">title</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><st rong><font color="#006699"><span class="tag"><span class="tag-name">content</span><span class="tag">></span></span></font><span>Here it is your first DOM application...</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">content</span><span class="tag">></span></font></strong><span> </span><li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag">subchapter_IV_I</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">title</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag-" name>chapter_IV</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span> </span><strong><font color="#006699"><span class="tag"><span class="tag-" name>end</span><span class="tag">></span></span></font></strong><span>The end...</span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">end</span><span class="tag">></span></font></strong><span> </span> </li> <li class="alt"> <span> </span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">contents</span><span class="tag">></span></font></strong><span> </span> </li> <li> <span></span><span class="comments"><font color="#008200"><!-- See you in XML Processing [part II] --></font></span><span> </span> </li> <li class="alt"> <span></span><strong><font color="#006699"><span class="tag"></span><span class="tag-name">book</span><span class="tag">></span></font></strong><span> </span> </li></st> </li> </ol>
First download the PHP code compression package used in this article,
Optimize PHP Code: Reducing Memory Usage & Execution TimeMay 10, 2025 am 12:04 AMTooptimizePHPcodeforreducedmemoryusageandexecutiontime,followthesesteps:1)Usereferencesinsteadofcopyinglargedatastructurestoreducememoryconsumption.2)LeveragePHP'sbuilt-infunctionslikearray_mapforfasterexecution.3)Implementcachingmechanisms,suchasAPC
PHP Email: Step-by-Step Sending GuideMay 09, 2025 am 12:14 AMPHPisusedforsendingemailsduetoitsintegrationwithservermailservicesandexternalSMTPproviders,automatingnotificationsandmarketingcampaigns.1)SetupyourPHPenvironmentwithawebserverandPHP,ensuringthemailfunctionisenabled.2)UseabasicscriptwithPHP'smailfunct
How to Send Email via PHP: Examples & CodeMay 09, 2025 am 12:13 AMThe best way to send emails is to use the PHPMailer library. 1) Using the mail() function is simple but unreliable, which may cause emails to enter spam or cannot be delivered. 2) PHPMailer provides better control and reliability, and supports HTML mail, attachments and SMTP authentication. 3) Make sure SMTP settings are configured correctly and encryption (such as STARTTLS or SSL/TLS) is used to enhance security. 4) For large amounts of emails, consider using a mail queue system to optimize performance.
Advanced PHP Email: Custom Headers & FeaturesMay 09, 2025 am 12:13 AMCustomheadersandadvancedfeaturesinPHPemailenhancefunctionalityandreliability.1)Customheadersaddmetadatafortrackingandcategorization.2)HTMLemailsallowformattingandinteractivity.3)AttachmentscanbesentusinglibrarieslikePHPMailer.4)SMTPauthenticationimpr
Guide to Sending Emails with PHP & SMTPMay 09, 2025 am 12:06 AMSending mail using PHP and SMTP can be achieved through the PHPMailer library. 1) Install and configure PHPMailer, 2) Set SMTP server details, 3) Define the email content, 4) Send emails and handle errors. Use this method to ensure the reliability and security of emails.
What is the best way to send an email using PHP?May 08, 2025 am 12:21 AMThebestapproachforsendingemailsinPHPisusingthePHPMailerlibraryduetoitsreliability,featurerichness,andeaseofuse.PHPMailersupportsSMTP,providesdetailederrorhandling,allowssendingHTMLandplaintextemails,supportsattachments,andenhancessecurity.Foroptimalu
Best Practices for Dependency Injection in PHPMay 08, 2025 am 12:21 AMThe reason for using Dependency Injection (DI) is that it promotes loose coupling, testability, and maintainability of the code. 1) Use constructor to inject dependencies, 2) Avoid using service locators, 3) Use dependency injection containers to manage dependencies, 4) Improve testability through injecting dependencies, 5) Avoid over-injection dependencies, 6) Consider the impact of DI on performance.
PHP performance tuning tips and tricksMay 08, 2025 am 12:20 AMPHPperformancetuningiscrucialbecauseitenhancesspeedandefficiency,whicharevitalforwebapplications.1)CachingwithAPCureducesdatabaseloadandimprovesresponsetimes.2)Optimizingdatabasequeriesbyselectingnecessarycolumnsandusingindexingspeedsupdataretrieval.
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),
MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.
Atom editor mac version download
The most popular open source editor
SublimeText3 Mac version
God-level code editing software (SublimeText3)
SublimeText3 Chinese version
Chinese version, very easy to use
