A common use for serialize is processing data without rebuilding the operation manually. Converts PHP values and objects into a PHP-specific serialized representation.
What Is serialize in PHP?
Converts PHP values and objects into a PHP-specific serialized representation.
Syntax:
serialize(?mixed $value) : string
Parameters and Return Value
$value— A required mixed input for this operation. Verify the allowed values in the examples and context below.
Declared return type: string. Distinguish false, an empty result, and exceptions where the API permits them.
Example 1: Basic Usage
This example demonstrates the main operation with a small, controlled input.
<?php
echo serialize(["name" => "Alex"]);
The example focuses on the value produced or the state changed by this API. Review the return value and validate input before using this pattern in production.
Example 2: Another Input
This example changes the input or surrounding setup to illustrate another behavior.
<?php
echo serialize([10, 20]);
The example focuses on the value produced or the state changed by this API. Review the return value and validate input before using this pattern in production.
Practical Example
This application-style example shows a self-contained usage pattern and checks its result.
<?php
$settings = ["theme" => "dark", "items" => 3];
$serializedSettings = serialize($settings);
echo strlen($serializedSettings);
The example focuses on the value produced or the state changed by this API. Review the return value and validate input before using this pattern in production.
Important Behavior and Edge Cases
- Prefer JSON for untrusted interchange; do not pass untrusted serialized text into unrestricted unserialize().
- Use the intended input type and handle empty or malformed values explicitly.
- Where this API requires an extension, version, or file, document that dependency before using it in a real application.
Comparison With Related Functions
| Function or Method | When to Use It |
|---|---|
serialize | Converts PHP values and objects into a PHP-specific serialized representation. |
json_encode | Converts PHP data to JSON text for APIs, data exchange and storage. |
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
| Using this API without checking the required input or extension | Prefer JSON for untrusted interchange; do not pass untrusted serialized text into unrestricted unserialize(). |
| Deserializing arbitrary user-provided bytes | Prefer JSON for public data, and never instantiate untrusted serialized objects. |
| Confusing an object’s serialize() format with JSON | Use the matching class and serialization API when restoring trusted data. |
Key Takeaways
- Converts PHP values and objects into a PHP-specific serialized representation.
- Prefer JSON for untrusted interchange; do not pass untrusted serialized text into unrestricted unserialize().
- Test both the expected case and at least one failure or empty-input case before deployment.
Converts PHP values and objects into a PHP-specific serialized representation. Use it when the operation fits your input, output and validation requirements.