<?php
/**
* Returns the value of an array key after checking to make sure it exists. May
* also check the value's type, make sure the value is in an array of allowed
* values and/or make sure the value is not NULL.
*
* @param array $array Array that should contain the key to return the value of.
* @param string|int $key Array key to return the value of.
* @param array $options Array of options. Possible keys are:
*
* type (string) - If included, must be 'string', 'numeric' or 'object'. If
* array key's value is not specified type, default value or NULL will be
* returned.
*
* class_name (string) - If type must be 'object', can also make sure array
* key's value is an instance of a specific class. If not, default value or
* NULL will be returned.
*
* value_array (array) - Array of values. If included, array key's value must
* match one of the values in this array. If not, default value or NULL will
* be returned.
*
* value_array_check_type (bool) - If value_array is included, can set this
* key to TRUE to enforce type checking when comparing array key's value to
* array of allowed values. If value_array is included and
* value_array_check_type is not included, types will not be checked when
* comparing the array key's value to the array of allowed values.
*
* default (any) - Optional default value to set array key's value to if any
* of the checks fail. If not included, default value will be NULL.
*
* allow_null (bool) - Whether or not array key's value may be NULL. If
* allow_null is FALSE and array key's value is NULL or ends up being set to
* NULL when one of the checks fails, an exception will be thrown.
*
* @return any Value of array key or default value if any of the checks fail.
*/
function get_value($array, $key, $options = array())
{
if ( ! is_array($array))
{
throw new Exception('Argument $array must be an array.');
}
if (( ! is_string($key)) && ( ! is_int($key)))
{
throw new Exception('Argument $key must be a string or an integer.');
}
if ( ! is_array($options))
{
throw new Exception('Argument $options must be an array.');
}
$value_is_valid = TRUE;
# existence check
if (( ! isset($array[$key])) && ( ! array_key_exists($key, $array)))
{
$value_is_valid = FALSE;
}
# type check
if ($value_is_valid)
{
if (isset($options['type']) && (in_array($options['type'], array('string', 'numeric', 'object'))))
{
$data_type_check_function = 'is_' . $options['type'];
if ($data_type_check_function($array[$key]))
{
if ($options['type'] === 'object')
{
if (isset($options['class_name']) && is_string($options['class_name']))
{
if (get_class($array[$key]) !== $options['class_name'])
{
$value_is_valid = FALSE;
}
}
}
}
else
{
$value_is_valid = FALSE;
}
}
}
# value check
if ($value_is_valid)
{
if (isset($options['value_array']) && is_array($options['value_array']))
{
if (( ! isset($options['value_array_check_type'])) || ($options['value_array_check_type'] !== TRUE))
{
$options['value_array_check_type'] = FALSE;
}
if ( ! in_array($array[$key], $options['value_array'], $options['value_array_check_type']))
{
$value_is_valid = FALSE;
}
}
}
# determine potential return value
if ($value_is_valid)
{
$return_value = $array[$key];
}
elseif (isset($options['default']) || array_key_exists('default', $options))
{
$return_value = $options['default'];
}
else
{
$return_value = NULL;
}
# determine if null return values are allowed
if (( ! isset($options['allow_null'])) || ($options['allow_null'] !== TRUE))
{
$options['allow_null'] = FALSE;
}
# null check
if (($return_value === NULL) && ( ! $options['allow_null']))
{
throw new Exception('Return value was determined to be NULL but NULL return values are not allowed.');
}
return $return_value;
}
<?php
$my_array = array();
$my_array['id'] = 1;
$my_array['action'] = 'Delete';
echo get_value($my_array, 'id', array('type' => 'numeric'));
# 1
echo get_value($my_array, 'action', array('type' => 'string', 'value_array' => array('Add', 'Edit', 'View'), 'default' => 'View'));
# View
try
{
echo get_value($my_array, 'action', array('type' => 'string', 'value_array' => array('Add', 'Edit', 'View')));
}
catch(Exception $e)
{
echo $e->getMessage();
}
# Return value was determined to be NULL but NULL return values are not allowed.
echo get_value($my_array, 'some_other_key', array('default' => 'Some other value...'));
# Some other value...
try
{
echo get_value($my_array, 'some_other_key');
}
catch(Exception $e)
{
echo $e->getMessage();
}
# Return value was determined to be NULL but NULL return values are not allowed.
echo get_value($my_array, 'some_other_key', array('allow_null' => TRUE));
# (NULL)
Refactorings
No refactoring yet !
Ants
January 8, 2011, January 08, 2011 06:42, permalink
No rating.
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The following is untested, but hopefully you get the drift of what the refactoring is trying to do...
<?php
function get_value($array, $key, $options = array())
{
if ( ! is_array($array))
{
throw new Exception('Argument $array must be an array.');
}
if (( ! is_string($key)) && ( ! is_int($key)))
{
throw new Exception('Argument $key must be a string or an integer.');
}
if ( ! is_array($options))
{
throw new Exception('Argument $options must be an array.');
}
$return_value = NULL;
if (array_key_exists($key, $array) && isset($array[$key]))
{
$return_value = $array[$key];
}
elseif (array_key_exists('default', $options))
{
$return_value = $options['default'];
}
# type check
if ( $return_value !== NULL
&& isset($options['type'])
&& in_array($options['type'], array('string', 'numeric', 'object')))
{
$data_type_check_function = 'is_' . $options['type'];
if ( ! $data_type_check_function($return_value)
|| ( $options['type'] === 'object'
&& isset($options['class_name']
&& is_string($options['class_name'])
&& get_class($return_value) !== $options['class_name']))
{
$return_value = NULL;
}
}
# value check
if ( $return_value !== NULL
&& isset($options['value_array'])
&& is_array($options['value_array'])
&& ! in_array($return_value, $options['value_array'], $options['value_array_check_type'] === TRUE))
{
$return_value = NULL;
}
# null check
if ( $return_value === NULL
&& isset($options['allow_null'])
&& $options['allow_null'] !== TRUE )
{
throw new Exception('Return value was determined to be NULL but NULL return values are not allowed.');
}
return $return_value;
}
Hi, I am looking for a code review of a function. Any suggestions as to how I can make it more efficient (faster) while maintaining the same functionality would be greatly appreciated. Thanks for taking a look!