When debugging in a PHP project, we often need to see which constants are currently defined, especially in large projects or environments where multiple third-party libraries are integrated. get_defined_constants() is a built-in function provided by PHP that can help us get all defined constants, including system default, extended loaded, and user-defined constants. This article will introduce how to use this function to build a simple and practical debugging dashboard to help developers quickly understand system status and configuration information.

Why does imageantialias() have no intensity parameters? The anti-aliasing function design of the GD library is relatively simple, and only supports on and off. The underlying implementation is controlled by the GD library itself, and there is no fine-grained adjustment interface exposed. Therefore, you cannot directly adjust the degree of anti-aliasing through imageantialias().

When processing user input or dynamically generated content, PHP developers often need to replace strings, while ensuring that this data remains structurally complete and secure when transmitted using json_encode() on the front end. mb_eregi_replace is a function in PHP multi-byte string extension mbstring that is more reliable than traditional preg_replace when dealing with multilingual or Unicode strings. This article will introduce how to use mb_eregi_replace to replace data and combine json_encode() to achieve secure data transmission.

The mb_eregi_replace function used to be one of my common tools when using PHP for string processing. This function can implement regular case-insensitive replacement of multi-byte strings, which is very suitable for processing text containing multi-byte characters such as Chinese. However, in the PHP 7.3+ environment, I suddenly found that using mb_eregi_replace in the code would cause warnings or even errors. I thought this function had been deprecated, but later I studied it in depth and found that the truth was not the case.

This article provides a detailed guide on how to implement the Observer Pattern using the Event Manager in the Phalcon framework. With practical code examples, it explains how to create event listeners, bind them to events, and trigger events to enable loose coupling in your application architecture.

This guide explains how to use the PHP language and the php-ml library to build a time series analysis and forecasting model. It covers data import, preprocessing, model construction, and result visualization, helping developers understand the fundamentals of time series modeling in PHP.

This article provides a comprehensive guide to building a microservices architecture using PHP. It covers API design, service development, container deployment, and monitoring — ideal for developers looking to implement scalable and resilient systems.

Preprocessing statements provide a safe way to prevent SQL injection attacks when using PHP for database operations. Using the mysqli extension, you can execute preprocessing statements through the mysqli_stmt object. When executing preprocessing statements, it is sometimes necessary to determine whether the statement is successfully executed. mysqli::$errno and mysqli_stmt are powerful tools for us to judge execution failures.

This article provides a detailed explanation of PHP’s built-in strpos() function, illustrating how to find the position of specific characters or substrings within a string through code examples, helping developers quickly master string handling techniques and improve coding efficiency.

This article provides a detailed guide on using the ThinkORM framework to easily carry out database migration and synchronization in PHP projects. It covers installation, configuration, migration file creation, execution, and multi-database synchronization setup, helping developers simplify data management and improve development efficiency.

imageopenpolygon() is a very interesting function that allows you to draw open (not closed) polygons through a set of coordinate points. This is especially useful when you need to draw complex graphics, such as star or snowflake patterns.

This article explores how to use Symfony’s middleware system to develop embedded APIs and microservices in PHP applications. It’s designed for developers seeking to improve system modularity and development efficiency.

A common requirement for processing images is to convert images in different formats into one of the common formats, such as PNG. The GD image library provides powerful functions to handle various image formats, where imagecreatefromgd2() can be used to read image files in .gd2 format, while imagepng() can output images to PNG format.

In PHP development, pack() and bin2hex() are two built-in functions commonly used for data processing and encoding conversion, and are especially useful in handling binary data, network transmission, file structure packaging and other scenarios. This article will introduce in detail the usage of these two functions and how to combine them to implement data encoding conversion.

This article explains how to use PHP to check if a remote FTP server is available, including connecting, logging in, performing test commands, and closing the connection—helping developers ensure FTP services are running smoothly.

This article provides a detailed tutorial on building a book recommendation site using PHP and Typecho. From environment setup and theme development to database integration and styling, it helps beginners quickly create a fully functional and clean-looking book recommendation platform.

This article provides a comprehensive guide to reading, writing, and managing files in PHP. It covers how to open and close files, read and write data, rename, copy, delete, and check file existence with practical code examples—ideal for both beginners and experienced developers.

In PHP, file hash calculation is usually used in scenarios such as data integrity verification, file deduplication, digital signatures, etc. When processing large files, hash_file() and hash_update_stream() are common hash calculation methods. Although the two have similar functions, there are some differences in performance. This article will compare the performance differences between these two methods when processing large files, helping developers better choose the right functions to improve the efficiency of their applications.

This article provides a detailed explanation of PHP's array_search() function, including its syntax, parameters, return values, and practical examples. It helps developers understand how to locate a key in an array by its value efficiently, making it a valuable tool for improving array handling in PHP.

imagecreatefromgd2() is a function used to create image resources from an image file in .gd2 format. However, this function often directly contacts and issues warnings or even causes script interruption when processing non-existent files, invalid formats, or corrupted images. In order to improve the robustness of the code, we can write a wrapper function, adding exception handling and error detection logic to make it more stable and reliable.