error() public static method Prints text to STDERR appended with a carriage return (PHP_EOL). public static integer|boolean error ( $string = null )$string string The text to print return integer|boolean Number of bytes printed or false on error.

validateDb() public method Validates the $db attribute. public void validateDb ( )

addValues() protected method Adds multiple key-value pairs to cache. The default implementation calls addValue() multiple times add values one by one. If the underlying cache storage supports multiadd, this method should be overridden to exploit that feature. protected array addValues ( $data, $duration )$data array Array where key corresponds to cache key while value is the value stored $duration integer The number of seconds in which the cached values will expire. 0 means never expir

refreshIndex() public method See also http://www.elastic.co/guide/en/elasticsearch/reference/current/indices-refresh.html. public mixed refreshIndex ( $index )$index

checkRequirements() public static method Checks if there is graphic extension available to generate CAPTCHA images. This method will check the existence of ImageMagick and GD extensions. public static string checkRequirements ( )return string The name of the graphic extension, either "imagick" or "gd". throws yii\base\InvalidConfigException if neither ImageMagick nor GD is installed.

$from public property The table(s) to be selected from. For example, ['user', 'post']. This is used to construct the FROM clause in a SQL statement. See also from(). public array $from = null

get() public method Retrieves a value from cache with a specified key. public mixed get ( $key )$key mixed A key identifying the cached value. This can be a simple string or a complex data structure consisting of factors representing the key. return mixed The value stored in cache, false if the value is not in the cache, expired, or the dependency associated with the cached data has changed.

$retryInterval public property How often a failed server will be retried (in seconds). This is used by memcache only. public integer $retryInterval = 15

activeTextarea() public static method Generates a textarea tag for the given model attribute. The model attribute value will be used as the content in the textarea. public static string activeTextarea ( $model, $attribute, $options = [] )$model yii\base\Model The model object $attribute string The attribute name or expression. See getAttributeName() for the format about attribute expression. $options array The tag options in terms of name-value pairs. These will be rendered as the at

renderDataCell() public method Renders a data cell. public string renderDataCell ( $model, $key, $index )$model mixed The data model being rendered $key mixed The key associated with the data model $index integer The zero-based index of the data item among the item array returned by yii\grid\GridView::$dataProvider. return string The rendering result