check_box
Github

	function check_box() {
		return _class('html')->check_box('input_name', ['k1' => 'key1', 'k2' => 'key2']);
	}
	function check_box($name = '', $value = '', $selected = '', $add_str = '', $extra = []) {
		if (is_array($name)) {
			$extra = (array)$extra + $name;
			$name = $extra['name'];
		}
		if (!is_array($extra)) {
			$extra = [];
		}
		$extra['name'] = strlen($name) ? $name : (strlen($extra['name']) ? $extra['name'] : 'checkbox');
		$extra['value'] = strlen($value) ? $value : (strlen($extra['value']) ? $extra['value'] : '1');
		$selected = isset($extra['selected']) ? $extra['selected'] : $selected;
		if (isset($extra['checked'])) {
			$selected = $extra['checked'];
		}
		$extra['checked'] = $selected ? 'checked' : null;
		$extra['id'] = ($extra['force_id'] ?: $extra['id']) ?: ($this->AUTO_ASSIGN_IDS ? __FUNCTION__.'_'.++$this->_ids[__FUNCTION__] : null);
		$extra['desc'] = isset($extra['desc']) ? $extra['desc'] : ucfirst(str_replace('_', '', $extra['name']));
		if ($extra['no_desc']) {
			$extra['desc'] = '';
		}
		$extra['class'] = trim($extra['class'].' '.$extra['class_add']);
		$add_str = $extra['add_str'] ? $extra['add_str'] : $add_str;
		$translate = $extra['translate'] ? $extra['translate'] : $translate;

		$label_extra = $extra['label_extra'];
		$def_label_class = $this->CLASS_LABEL_CHECKBOX.' '.$this->CLASS_LABEL_CHECKBOX_INLINE;
		$label_extra['class'] = isset($label_extra['class']) ? $label_extra['class'] : (isset($extra['class_label_checkbox']) ? $extra['class_label_checkbox'] : $def_label_class);
		if ($extra['class_add_label_checkbox']) {
			$label_extra['class'] .= ' '.$extra['class_add_label_checkbox'];
		}
		if ($selected) {
			$label_extra['class'] .= ' '.$this->CLASS_LABEL_CHECKBOX_SELECTED;
		}
		$body = [];
		if ($extra['outer_label']) {
			$body[] = '<label class="outer-label">'.$extra['outer_label'].'</label>';
		}
		$extra['type'] = 'checkbox';
		$body[] = '<label'._attrs($label_extra, ['id', 'class', 'style']).'>'
				. '<input'._attrs($extra, ['type','name','id','value','checked','class','style','disabled','required']). ($add_str ? ' '.$add_str : '')
				. '>  <span>'. ($translate ? t($extra['desc']) : $extra['desc']). '</span>' // Please do not remove whitespace before   :)
			. '</label>';
		return implode(PHP_EOL, $body);
	}