PHP FILTER_CALLBACKFilter
Complete PHP Filter Reference Manual
Definition and Usage
The FILTER_CALLBACK filter calls a user-defined function to filter data.
This filter provides us with complete control over data filtering.
The specified function must be stored in an associative array named "options". See the example below.
- Name: "callback"
- ID-number: 1024
Tips and Notes
Tip:You can create your own function, or use an existing PHP function.
Example 1
Using a user-defined function:
<?php
function convertSpace($string)
{
return str_replace(" ", "_", $string);
}
$string = "Peter is a great guy!";
echo filter_var($string, FILTER_CALLBACK,
array("options"=>"convertSpace"));
?>
function convertSpace($string)
{
return str_replace(" ", "_", $string);
}
$string = "Peter is a great guy!";
echo filter_var($string, FILTER_CALLBACK,
array("options"=>"convertSpace"));
?>
The output of the code is shown below:
Peter_is_a_great_guy!
Example 2
Using an existing PHP function:
<?php
$string="Peter is a great guy!";
echo filter_var($string, FILTER_CALLBACK,
array("options"=>"strtoupper"));
?>
$string="Peter is a great guy!";
echo filter_var($string, FILTER_CALLBACK,
array("options"=>"strtoupper"));
?>
The output of the code is shown below:
PETER IS A GREAT GUY!
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