Quick Reference
The PHP filter_input() function gets an external variable from insecure sources (e.g., user input) and optionally filters it to validate variables.
<?php
if (!filter_input(INPUT_GET, 'email', FILTER_VALIDATE_EMAIL)) {
echo('Email is not valid');
}
else {
echo('Email is valid');
}
?>Output
// checks if the external variable "email" is sent to the PHP page, through the "get" method, and also check if it is a valid email addressSyntax
filter_input(type, variable, filter, options)Parameters
| Parameter | Description |
|---|---|
| type | The input type to check for (required):
|
| variable | The variable name to check (required) |
| filter | Specifies the ID or name of the filter to use (default is FILTER_DEFAULT, which results in no filtering) |
| options | Specifies one or more flags/options to use |
PHP Notes:
- When using PHP, single or double quotation marks are acceptable and work identically to one another; choose whichever you prefer, and stay consistent
- Arrays count starting from zero NOT one; so item 1 is position [0], item 2 is position [1], and item 3 is position [2] … and so on
We’d like to acknowledge that we learned a great deal of our coding from W3Schools and TutorialsPoint, borrowing heavily from their teaching process and excellent code examples. We highly recommend both sites to deepen your experience, and further your coding journey. We’re just hitting the basics here at 1SMARTchicken.