PHP var_export()-PHP Tutorial-php.cn

PHP comes out a function of var_export that returns structured information about any variable. Whatever the variable is that is defined with var_export() comes up with structured information. The returned value of this function is a valid PHP code. This makes var_export a unique function from its defined function var_dump(). This var_export function of PHP came after the PHP 4 stable release version of PHP. The function only returns the value as the structured information of any variable.

Start Your Free Software Development Course

Web development, programming languages, Software testing & others

Syntax of PHP var_export()

Given below is the syntax of PHP var_export():

var_export(variable, return)

Copy after login

variable: The variable we want to export.
return: Optional parameter, if used, returns the variable representation.

A variable is a required parameter with String as the Data Type for that. Where as the return is the optional parameter as the Boolean Data Type.

Example:

<!DOCTYPE html>
<html>
<body>
<?php
$a = 3;
echo var_export($a, true) . "<br>";
echo var_export($a) . "<br>";
?>
</body>
</html>

Copy after login

Output:

PHP var_export()

Working of var_export() Function

The var_export() function takes up the input as the variable whose structured definition is to be checked. The return value depends on the return parameter (the optional one that is used and set to true).
If that is not done, the function will return null. When the return parameter is used, it uses the internal output buffering methodology that basically tells PHP to hold some data before it is sent to the browser. Having this, we can retrieve the data and manipulate it if needed to avoid the use of the call back function.
A valid PHP code with structured information about the variable is returned with this function.

Examples of PHP var_export()

Using PHP with basic Data Types as the example:

Example #1: Integer

This takes up Integer as the input as results the structured information about the variable as Integer.

Code:

<!DOCTYPE html>
<html>
<body>
<?php
$a = 320;
echo var_export($a) . "<br>";
$a = 2;
echo var_export($a) . "<br>";
$a = -32;
echo var_export($a) . "<br>";
$a = 3200;
echo var_export($a) . "<br>";
?>
</body>
</html>

Copy after login

Output:

PHP var_export()

Example #2: String

This takes up String as the input as result the structured information about the variable as String.

Code:

<!DOCTYPE html>
<html>
<body>
<?php
$b = "PHP Example!!";
echo var_export($b) . "<br>";
$b = "I am String";
echo var_export($b) . "<br>";
?>
</body>
</html>

Copy after login

Output:

PHP var_export()

Example #3: Double

This takes up Double/Decimal as the input as results the structured information about the variable as Double.

Code:

<!DOCTYPE html>
<html>
<body>
<?php
$a = 322.5;
echo var_export($a) . "<br>";
$a = 22.51;
echo var_export($a) . "<br>";
?>
</body>
</html>

Copy after login

Output:

PHP var_export()

Example #4: Array

This takes up Array as the input as results the structured information about the variable as Array.

Code:

<!DOCTYPE html>
<html>
<body>
<?php
$a = array("reddish", "yellowish", "Greenish");
echo var_export($a) . "<br>";
$a = array("Apple", "Grapes", "Mango");
echo var_export($a) . "<br>";
?>
</body>
</html>

Copy after login

Output:

PHP var_export()

Example #5: Array of Array

This takes up Array of Array as the input as results the structured information about the variable as Array.

Code:

<!DOCTYPE html>
<html>
<body>
<?php
$a = array("abc", "Hello PHP!", 222.4, array("reddish", "yellowish", "Greenish"));
echo var_export($a) . "<br>";
$a = array(34, "Hello", array("Apple", "Grapes", "3"));
echo var_export($a) . "<br>";
?>
</body>
</html>

Copy after login

Output:

We can even set an object and map it with a variable. Calling that particular in var_export function will give the state of an object.

Let us check that with an example :

Code:

<!DOCTYPE html>
<html>
<body>
<?php
$person = new stdClass;
$person->name = 'John Anand';
$person->website = 'https://php.net/John.php';
echo var_export($person);
?>
</body>
</html>

Copy after login

Output:

PHP var_export()

We can also define a class in PHP and use the var_export function that sets the state of the class variable.

Let us check that with an example :

Code:

<!DOCTYPE html>
<html>
<body>
<?php
class A { public $var; }
$a = new A;
$a->var = 50;
var_export($a);
echo var_export(a);
?>
</body>
</html>

Copy after login

Output:

PHP var_export()

Short Note

There are some points that need to be noted for the PHP var export function:

This VarExport Function does not export type Resource Variables.
The Circular references are also not handled by the VarExport function as the parsable PHP codes are not generated for circular references.
The processed object implements the _set_state method except for the stdClass, which is exported using an array that is casted with an object.

Conclusion

From the above article, we saw the use of Function var_export in PHP. We tried to see how the var_export() function works in PHP and what are is use at the programming level from various example and classification. We also saw the internal working and the advantages of having the type of data we define for various programming purposes. Also, the syntax and examples helped us to understand much precisely over the function.

The above is the detailed content of PHP var_export(). 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

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

How to fix KB5055523 fails to install in Windows 11?

3 weeks ago By DDD

How to fix KB5055518 fails to install in Windows 10?

3 weeks ago By DDD

Roblox: Dead Rails - How To Tame Wolves

4 weeks ago By DDD

Roblox: Grow A Garden - Complete Mutation Guide

2 weeks ago By DDD

Strength Levels for Every Enemy & Monster in R.E.P.O.

4 weeks ago By 尊渡假赌尊渡假赌尊渡假赌

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

Java Tutorial

1657

CakePHP Tutorial

1415

Laravel Tutorial

1309

PHP Tutorial

1257

C# Tutorial

1230

Related knowledge

PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian Dec 24, 2024 pm 04:42 PM

PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati

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. 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::). 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 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? 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 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: 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