Filters

Alpha

The Alpha filter can be used to return only alphabetic characters in the unicode "letter" category. All other characters are suppressed.

Basic Usage

$filter = new Zend\I18n\Filter\Alpha();

echo $filter->filter("This is (my) content: 123"); // "Thisismycontent"

By default, if no locale is provided, Alpha will use the system locale provide by PHP's Locale class and the getDefault() method.

Using Whitespace

To allow whitespace characters (\s) on filtering set the option to true; otherwise they are suppressed.

$filter = new Zend\I18n\Filter\Alpha(true);

echo $filter->filter("This is (my) content: 123"); // "This is my content"

$filter = new Zend\I18n\Filter\Alpha();
$filter->setAllowWhiteSpace(true);

echo $filter->filter("This is (my) content: 123"); // "This is my content"

Get Current Value

To get the current value of this option, use the getAllowWhiteSpace() method.

$filter = new Zend\I18n\Filter\Alpha(true);

var_dump($filter->getAllowWhiteSpace()); // true

Default Value

The default value of this option is false that means whitespace characters are suppressed.

Using Locale

The locale string used in identifying the characters to filter (locale name, e.g. en_US).

$filter = new Zend\I18n\Filter\Alpha(null, 'en_US');

echo $filter->filter("This is (my) content: 123"); // "Thisismycontent"

$filter = new Zend\I18n\Filter\Alpha();
$filter->setLocale('en_US');

echo $filter->filter("This is (my) content: 123"); // "Thisismycontent"

Locale::setDefault('en_US');

$filter = new Zend\I18n\Filter\Alpha();

echo $filter->filter("This is (my) content: 123"); // "Thisismycontent"

Get Current Value

To get the current value of this option, use the getLocale() method.

$filter = new Zend\I18n\Filter\Alpha(null, 'en_US');

echo $filter->getLocale(); // 'en_US'

Default Value

By default, if no locale is provided, Alpha will use the system locale provide by PHP's Locale::getDefault().

Supported languages

Alpha works for most languages, except Chinese, Japanese and Korean. Within these languages, the English alphabet is used instead of the characters from these languages. The language itself is detected using the Locale class.