PHP Class to consistently cast variables to a specific type.

2.1.0 2022-11-13 12:22 UTC

This package is auto-updated.

Last update: 2024-02-23 02:19:35 UTC


GitHub license CS Lint


PHP Class to consistently cast variables to a specific type.

Returns either the value in the specified type or null.


  • Consistent results across PHP versions.
  • Compatible with PHP4, PHP5 and PHP7 which makes it extra useful if you're coding for open source software where you don't know the library user's PHP version and the filter_var() functions may not be available.
  • Optionally recursively cast all values in an array to the choosen type (similar to filter_var_array() behaviour).
  • Optionally allow/disallow empty strings/arrays.
  • Will succesfully cast any of the following string values to their boolean counterpart (similar to filter_var() behaviour, but less case-sensitive).
    • True: '1', 'true', 'True', 'TRUE', 'y', 'Y', 'yes', 'Yes', 'YES', 'on', 'On', 'ON'.
    • False: '0', 'false', 'False', 'FALSE', 'n', 'N', 'no', 'No', 'NO', 'off', 'Off', 'OFF'.
  • Support for casting of SplType objects.

Some Usage examples:

$value = 'example';
$value = CastToType::_bool( $value ); // null

$value = 'true';
$value = CastToType::_bool( $value ); // true

$value = '123';
$value = CastToType::_int( $value ); // 123

$value = array( '123' );
$value = CastToType::_int( $value ); // null
$value = CastToType::_int( $value, $array2null = false ); // array( 123 )

Available methods:

All methods are static.

  • CastToType::cast( $value, $type, $array2null = true, $allow_empty = true, $implode_array = false );

  • CastToType::_bool( $value, $array2null = true, $allow_empty = true );

  • CastToType::_int( $value, $array2null = true, $allow_empty = true );

  • CastToType::_float( $value, $array2null = true, $allow_empty = true );

  • CastToType::_string( $value, $array2null = true, $allow_empty = true );

  • CastToType::_array( $value, $allow_empty = true );

  • CastToType::_object( $value, $allow_empty = true );

  • CastToType::_null( $value );


Param Type Description
$value mixed Value to cast.
$type string Type to cast to. Valid values: 'bool', 'boolean', 'int', 'integer', 'float', 'double', 'num', 'string', 'array', 'object'.
$array2null bool Optional. Whether to return null for arrays when casting to bool, int, float, num or string. If false, the individual values held in the array will recursively be cast to the specified type. Defaults to true.
$allow_empty bool Optional. Whether to allow empty strings, empty arrays, empty objects. If false, null will be returned instead of the empty string/array/object. Defaults to true.



This package requires the PHP native ctype extension.


  1. Head to the Releases page and download the latest release zip.
  2. Extract the files and place them somewhere in your project hierarchy.
  3. Require the class loader using require_once '/path/to/cast-to-type.php';.


If you are using PHP5+ (as you should), PHP-Cast-to_Type is also available as a package installable via Composer:

composer require jrfnl/PHP-cast-to-type


2.1.0 (Nov 2022)

  • Allow for double as an alias for float in the CastToType::cast() method. Thanks @nsrosenqvist for the contribution.
  • Bug fix: string ON not recognized as truthy when casting to boolean.
  • The requirement for the ctype extension has been made explicit.
  • The primary branch has been renamed from master to main.
  • General housekeeping.

2.0.1 (Jan 2018)

  • Bugfix for PHP cross-version compatibility. This affected use of this class on PHP < 5.2.7.
  • General housekeeping.

2.0 (Jun 2015)

  • Updated the object casting to be in line with the way this is done in PHP7 for cross-version compatibility. Previously arrays with numerical keys cast to objects would be added to the object as a property called array with the value being the complete array. Now - as in PHP7 - each numerical array key will be cast to an individual property. This breaks backward-compatibility with v1.0 for array to object cast results, so please review your code if you relied on the old behaviour.
  • Fixed a bug in the object casting which would return null for non-objects cast to objects in PHP <= 5.1.
  • Fixed a bug in the object casting where an empty string would not return null while $allow_empty was set to false.

1.0 (2006 / Sept 2013)

  • Initial release.