A common use for urldecode is processing data without rebuilding the operation manually. Decodes application/x-www-form-urlencoded text, converting plus signs to spaces.
What Is urldecode in PHP?
Decodes application/x-www-form-urlencoded text, converting plus signs to spaces.
Syntax:
urldecode(?string $string) : string
Parameters and Return Value
$string— A required string 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 urldecode("hello+world");
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 urldecode("name%3DAlex");
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
$decodedValue = urldecode("order+status%3Dopen");
echo $decodedValue;
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
- Do not decode request parameters repeatedly; PHP normally decodes $_GET and $_POST already.
- 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 |
|---|---|
urldecode | Decodes application/x-www-form-urlencoded text, converting plus signs to spaces. |
rawurldecode | Decodes percent-escaped characters in a URL component. |
Common Beginner Mistakes
| Mistake | Correct Approach |
|---|---|
| Using this API without checking the required input or extension | Do not decode request parameters repeatedly; PHP normally decodes $_GET and $_POST already. |
| Encoding an entire URL as a component | Encode only the relevant path segment or query value. |
| Using decoded values as paths without validation | Enforce safe path boundaries after decoding. |
Key Takeaways
- Decodes application/x-www-form-urlencoded text, converting plus signs to spaces.
- Do not decode request parameters repeatedly; PHP normally decodes $_GET and $_POST already.
- Test both the expected case and at least one failure or empty-input case before deployment.
Decodes application/x-www-form-urlencoded text, converting plus signs to spaces. Use it when the operation fits your input, output and validation requirements.