Backend Development
PHP Tutorial
An article detailing the principles of the PHP template engine (with code examples)
An article detailing the principles of the PHP template engine (with code examples)
Developing a web project is usually divided into two parts. One part is GUI, that is, interface and art, written using HTML, CSS, JS, and the other part is business logic, that is, programs and functions, written using PHP. The template engine is the "bridge" that connects the two parts. It can be understood as a PHP class, which defines many methods to load the original output of PHP into the interface style and then output it.
The code written before using the template is like this:
<?php $title = “标题”; $content = “内容”; ?> <html> <head><title><?php echo $title; ?></title></head> <body><?php echo $content; ?></body> </html>
In this way, there is no separation between art and logic. Simply put, PHP programmers must not only write programs but also be proficient in art. This It is often very difficult, so the two parts of the work need to be separated.
Let’s create a simple template engine as an example to better understand the principles of the template engine.
As mentioned before, developing a web project is divided into two parts: GUI and business logic, so we create two folders, one named "templates", which stores templates, create a new tpl.html file, and name the other For "PHP", which stores business logic, create a new index.php file.
tpl.html file code usually looks like this:
<html>
<head><title><{$title}></title></head>
<body><{ $content;}></body>
</html>It can be seen that compared with the previous code, tpl.html only has html code and no php code, but new ones have been added Tags, this type of tag is defined by yourself, and the content inside can only be recognized after being compiled by the template engine. The compiled files are stored in the "templates_c" folder. This file is mainly used for interface design, and will use a large number of CSS, JS and other technologies.
At this time, tpl.html and index.php are still separated and do not interfere with each other, so they need a "bridge" connection, that is, the template engine, which is actually a PHP class, so a mytpl can be created here. PHP file class.php.
The mytpl.class.php file usually defines a class MyTpl. An array tpl_var[] needs to be defined in the class to store the parameters of the custom content tag in tpl.html. In addition, some methods need to be defined. These methods The main purpose is to convert unrecognized content tags in tpl.hml into PHP statements, and then write them to tpl_c.html in a "templates_c" folder. This process is called compilation.
Usually the code of the tpl_c.html file is like this:
<html> <head><title><?php echo $this->tpl_var[“title”]; ?></head> <body><?php echo $this->tpl_var[“content”]; ?}></body> </html>
It can be seen that the above code can be recognized because the custom content tags have been replaced with PHP statements. But we still don’t know what the values of title and content are. At this time, the index.php created before will come into play.
index.php Usually its code is like this:
include “tpl.class.php文件”;//加载模板引擎 $tpl = new MyTpl();//实例化一个模板类 $title = “标题”; $content = “内容”; $tpl->assign(“title”,$title);//调用模板类中的方法，分配变量 $tpl->assign(“content”,$content); $tpl->display(“tpl.html”);//调用模板类中的方法，用于显示编译后的内容
The above code is just some simple description code. The values of the variables can be directly defined or obtained from the database. In addition, the file can also write some complex PHP programs, which is the business mentioned before. logic.
In this way, the work of GUI and business logic is separated. Art designers only need to write template files to change the web interface, while PHP programmers can concentrate on writing their own programs.
Companies generally have their own template engines, and there is usually no need to write the template engine yourself, because there are already some very mature template engines on the market, such as Smarty. We only need to know how to use it. Enough.
Recommended learning: "PHP Video Tutorial"
The above is the detailed content of An article detailing the principles of the PHP template engine (with code examples). For more information, please follow other related articles on the PHP Chinese website!
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
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1667
14
1426
52
1328
25
1273
29
1255
24
PHP: A Key Language for Web Development
Apr 13, 2025 am 12:08 AM
PHP is a scripting language widely used on the server side, especially suitable for web development. 1.PHP can embed HTML, process HTTP requests and responses, and supports a variety of databases. 2.PHP is used to generate dynamic web content, process form data, access databases, etc., with strong community support and open source resources. 3. PHP is an interpreted language, and the execution process includes lexical analysis, grammatical analysis, compilation and execution. 4.PHP can be combined with MySQL for advanced applications such as user registration systems. 5. When debugging PHP, you can use functions such as error_reporting() and var_dump(). 6. Optimize PHP code to use caching mechanisms, optimize database queries and use built-in functions. 7
PHP and Python: Comparing Two Popular Programming Languages
Apr 14, 2025 am 12:13 AM
PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.
PHP vs. Python: Understanding the Differences
Apr 11, 2025 am 12:15 AM
PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries.
PHP in Action: Real-World Examples and Applications
Apr 14, 2025 am 12:19 AM
PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved.
The Enduring Relevance of PHP: Is It Still Alive?
Apr 14, 2025 am 12:12 AM
PHP is still dynamic and still occupies an important position in the field of modern programming. 1) PHP's simplicity and powerful community support make it widely used in web development; 2) Its flexibility and stability make it outstanding in handling web forms, database operations and file processing; 3) PHP is constantly evolving and optimizing, suitable for beginners and experienced developers.
PHP vs. Other Languages: A Comparison
Apr 13, 2025 am 12:19 AM
PHP is suitable for web development, especially in rapid development and processing dynamic content, but is not good at data science and enterprise-level applications. Compared with Python, PHP has more advantages in web development, but is not as good as Python in the field of data science; compared with Java, PHP performs worse in enterprise-level applications, but is more flexible in web development; compared with JavaScript, PHP is more concise in back-end development, but is not as good as JavaScript in front-end development.
PHP and Python: Different Paradigms Explained
Apr 18, 2025 am 12:26 AM
PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning.
PHP and Python: Code Examples and Comparison
Apr 15, 2025 am 12:07 AM
PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning.
