Home Backend Development PHP Tutorial Detailed explanation of __FILE__ constant and dirname() instance usage in php

Detailed explanation of __FILE__ constant and dirname() instance usage in php

Jun 29, 2017 am 10:35 AM
dirname file php

dirname(FILE_) The function returns the path where the script is located.
For example, the file b.php contains the following content:

1

2

3

<?php

$basedir = dirname(FILE);

?>

Copy after login

If b.php is used by a.php file in another directory require or include Go to and quote .
The content of the variable $basedir is still the path to the folder where b.php is located.
Instead of changing to the directory where the a.php file is located.
dirname(FILE) generally returns a directory structure from the current directory where the file is located to the system root directory.
The current file name will not be returned.
dirname(FILE) may also return a . (current directory)
[The reason is that the b.php file is in the default WEB directory of http.conf or PHP Configuring the development environment .
For example, WEB_ROOT is: "C:/root/www/".]
b.php file path is: "C:/root/www/b.php".

Usage tips,
If you repeat it once, you can move the directory up a level:
For example: $d = dirname(dirname(FILE));
In fact, you give a directory as a parameter to dirname(). Because dirname() returns the last directory without \\ or /
, when it is used repeatedly, it can be considered that dirname() treats the lowest directory as a file name. Return
the upper-level directory of the current directory as usual. Repeat this to get its upper-level directory.

Contains the files that get the upper-level directory

1

include(dirname(FILE).&#39;/../filename.php&#39;);

Copy after login

2. How to use PHP files and html files together

1

2

3

4

5

6

7

8

<?php

if($reguser != ""){

  echo"Submit Photo ";

  echo"Log Out";

}else{

  echo"Login";

}

?>

Copy after login

FILE represents the absolute path of the current file including the file name, dirname(FILE) represents the absolute path of the current file, basename(FILE) represents The file name of the current file, dirname(FILE)."/f/".basename(FILE) means a file with the file name dirname(FILE) in the f directory under the directory where the current file is located. require means that the file is included in this file.

1) The dirname(FILE_) function returns the path where the script is located.
For example, the file b.php contains the following content:
$basedir = dirname(FILE);
?>
If b.php is replaced by a in another directory. PHP file require or include to quote.
The content of the variable $basedir is still the path to the folder where b.php is located.
Instead of becoming the directory where the a.php file is located.

2) dirname(FILE) generally returns a directory structure from the current directory where the file is located to the system root directory.
Will not return the current file name.
dirname(FILE) may also return one. (current directory)
[The reason is that the b.php file is in http.conf or the default WEB directory of the PHP configuration development environment.
For example, WEB_ROOT is: "C :/root/www/".]
The path to the b.php file is: "C:/root/www/b.php".

3) Usage tips,
If repeated You can raise the directory to a higher level:
For example: $d = dirname(dirname(FILE));
In fact, you just give a directory as a parameter to dirname(). Because dirname() returns the last directory without \\ or /
, so when it is used repeatedly, it can be considered that dirname() treats the lowest directory as a file name. Return as usual
The superior directory of the current directory. Repeat this to get its superior directory.

The above is the detailed content of Detailed explanation of __FILE__ constant and dirname() instance usage in php. For more information, please follow other related articles on the PHP Chinese website!

Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Tools

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Zend Studio 13.0.1

Zend Studio 13.0.1

Powerful PHP integrated development environment

Dreamweaver CS6

Dreamweaver CS6

Visual web development tools

SublimeText3 Mac version

SublimeText3 Mac version

God-level code editing software (SublimeText3)

Hot Topics

Java Tutorial
1662
14
PHP Tutorial
1261
29
C# Tutorial
1234
24
How do you parse and process HTML/XML in PHP? How do you parse and process HTML/XML in PHP? Feb 07, 2025 am 11:57 AM

This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an

Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Explain JSON Web Tokens (JWT) and their use case in PHP APIs. Apr 05, 2025 am 12:04 AM

JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,

Explain late static binding in PHP (static::). Explain late static binding in PHP (static::). Apr 03, 2025 am 12:04 AM

Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.

PHP Program to Count Vowels in a String PHP Program to Count Vowels in a String Feb 07, 2025 pm 12:12 PM

A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total

What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases? Apr 03, 2025 am 12:03 AM

What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.

PHP and Python: Comparing Two Popular Programming Languages 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 in Action: Real-World Examples and Applications 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.

PHP: A Key Language for Web Development 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

See all articles