FractionDecimal.php in Fraction 2.x
Same filename and directory in other branches
Namespace
Drupal\fraction\ElementFile
src/Element/FractionDecimal.phpView source
<?php
namespace Drupal\fraction\Element;
use Drupal\Core\Form\FormStateInterface;
use Drupal\Core\Render\Element;
use Drupal\Core\Render\Element\FormElement;
use Drupal\Core\Render\Element\Number;
use Drupal\fraction\Fraction;
/**
* Provides a fraction decimal form element.
*
* Usage example:
* @code
* $form['fraction'] = [
* '#type' => 'fraction_decimal',
* '#title' => $this->t('Fraction'),
* '#default_value' => 10.385,
* '#size' => 60,
* '#required' => TRUE,
* ];
* @endcode
*
* @FormElement("fraction_decimal")
*/
class FractionDecimal extends FormElement {
/**
* {@inheritdoc}
*/
public function getInfo() {
$class = get_class($this);
return [
'#input' => TRUE,
'#step' => 'any',
'#size' => 15,
'#maxlength' => 128,
'#default_value' => NULL,
'#element_validate' => [
[
$class,
'validateDecimal',
],
],
'#process' => [
[
$class,
'processAjaxForm',
],
[
$class,
'processGroup',
],
],
'#pre_render' => [
[
$class,
'preRenderNumber',
],
[
$class,
'preRenderGroup',
],
],
'#theme' => 'input__textfield',
'#theme_wrappers' => [
'form_element',
],
];
}
/**
* Validates the fraction_decimal element.
*
* @param array $element
* The form element.
* @param \Drupal\Core\Form\FormStateInterface $form_state
* The current state of the form.
* @param array $complete_form
* The complete form structure.
*/
public static function validateDecimal(array $element, FormStateInterface $form_state, array &$complete_form) {
$value = trim($element['#value']);
// Only continue with validation if the value is not empty.
if ($element['#value'] === '') {
return;
}
// Do basic number validations.
Number::validateNumber($element, $form_state, $complete_form);
// Only continue with validation if value is a valid number.
if (count($form_state
->getErrors()) !== 0) {
return;
}
// Convert the value to a fraction.
$fraction = Fraction::createFromDecimal($value);
// Get the numerator and denominator.
$numerator = $fraction
->getNumerator();
$denominator = $fraction
->getDenominator();
// Set the numerator and denominator values for the form.
$values = [
'decimal' => $value,
'numerator' => $numerator,
'denominator' => $denominator,
];
$form_state
->setValueForElement($element, $values);
// The maximum number of digits after the decimal place is 9.
// Explicitly perform a string comparison to ensure precision.
if ((string) $denominator > '1000000000') {
$form_state
->setError($element, t('The maximum number of digits after the decimal place is 9.'));
}
// Ensure that the decimal value is within an acceptable value range.
// Convert the fraction back to a decimal, because that is what will be
// stored. Explicitly perform a string comparison to ensure precision.
$decimal = (string) $fraction
->toDecimal(0, TRUE);
$min_decimal_fraction = new Fraction('-9223372036854775808', $denominator);
$min_decimal = (string) $min_decimal_fraction
->toDecimal(0, TRUE);
$max_decimal_fraction = new Fraction('9223372036854775807', $denominator);
$max_decimal = (string) $max_decimal_fraction
->toDecimal(0, TRUE);
$scale = strlen($denominator) - 1;
$in_bounds = static::checkInBounds($decimal, $min_decimal, $max_decimal, $scale);
if (!$in_bounds) {
$form_state
->setError($element, t('The number you entered is outside the range of acceptable values. This limitation is related to the decimal precision, so reducing the precision may solve the problem.'));
}
}
/**
* Prepares a #type 'fraction_decimal' render element for input.html.twig.
*
* @param array $element
* An associative array containing the properties of the element.
* Properties used: #title, #value, #description, #size, #maxlength,
* #placeholder, #required, #attributes.
*
* @return array
* The $element with prepared variables ready for input.html.twig.
*/
public static function preRenderNumber(array $element) {
$element['#attributes']['type'] = 'text';
Element::setAttributes($element, [
'id',
'name',
'value',
'size',
'maxlength',
'placeholder',
]);
static::setAttributes($element, [
'form-text',
]);
return $element;
}
/**
* Helper method to check if a given value is in between two other values.
*
* Uses BCMath and strings for arbitrary-precision operations where possible.
*
* @param string $value
* The value to check.
* @param string $min
* The minimum bound.
* @param string $max
* The maximum bound.
* @param int $scale
* Optional scale integer to pass into bcsub() if BCMath is used.
*
* @return bool
* Returns TRUE if $number is between $min and $max, FALSE otherwise.
*/
public static function checkInBounds($value, $min, $max, $scale = 0) {
// If BCMath isn't available, let PHP handle it via normal float comparison.
if (!function_exists('bcsub')) {
return $value > $max || $value < $min ? FALSE : TRUE;
}
// Subtract the minimum bound and maximum bounds from the value.
$diff_min = bcsub($value, $min, $scale);
$diff_max = bcsub($value, $max, $scale);
// If either have a difference of zero, then the value is in bounds.
if ($diff_min == 0 || $diff_max == 0) {
return TRUE;
}
// If the first character of $diff_min is a negative sign (-), then the
// value is less than the minimum, and therefore out of bounds.
if (substr($diff_min, 0, 1) == '-') {
return FALSE;
}
// If the first character of $diff_max is a number, then the value is
// greater than the maximum, and therefore out of bounds.
if (is_numeric(substr($diff_max, 0, 1))) {
return FALSE;
}
// Assume the value is in bounds if none of the above said otherwise.
return TRUE;
}
}
Classes
Name | Description |
---|---|
FractionDecimal | Provides a fraction decimal form element. |