silverstripe-framework/forms/FormTemplateHelper.php

<?php

/**
 * A helper class for managing {@link Form} and {@link FormField} HTML template
 * output.
 *
 * This primarily exists to maintain backwards compatibility between Form and
 * FormField template changes since developers may rely on specific HTML output
 * in their applications. Any core changes to templates (such as changing ID's)
 * may have the potential to silently prevent websites from working.
 *
 * To provide a form with a custom FormTemplateHelper use the following snippet:
 *
 * <code>
 * $form->setTemplateHelper('ClassName');
 * </code>
 *
 * Globally, the FormTemplateHelper can be set via the {@link Injector} API.
 *
 * For backwards compatibility, with < 3.2 use the {@link FormTemplateHelper_Pre32}
 * class which will preserve the old style form field attributes.
 *
 * <code>
 *	Injector:
 *	  FormTemplateHelper:
 *	    class: FormTemplateHelper_Pre32
 * </code>
 *
 * @package framework
 * @subpackage forms
 */
class FormTemplateHelper {

	/**
	 * @param Form $form
	 *
	 * @return string
	 */
	public function generateFormID($form) {
		if($id = $form->getHTMLID()) {
			return Convert::raw2htmlid($id);
		}

		return Convert::raw2htmlid(
			get_class($form) . '_' . str_replace(array('.', '/'), '', $form->getName())
		);
	}

	/**
	 * @param FormField $field
	 *
	 * @return string
	 */
	public function generateFieldHolderID($field) {
		return $this->generateFieldID($field) . '_Holder';
	}

	/**
	 * Generate the field ID value
	 *
	 * @param FormField
	 *
	 * @return string
	 */
	public function generateFieldID($field) {
		if($form = $field->getForm()) {
			return sprintf("%s_%s",
				$this->generateFormID($form),
				Convert::raw2htmlid($field->getName())
			);
		}

		return Convert::raw2htmlid($field->getName());
	}

}

/**
 * Note that this will cause duplicate and invalid ID attributes.
 *
 * @deprecated 4.0
 *
 * @package framework
 * @subpackage forms
 */
class FormTemplateHelper_Pre32 extends FormTemplateHelper {

	/**
	 * @param Form
	 *
	 * @return string
	 */
	public function generateFormID($form) {
		if($id = $form->getHTMLID()) {
			return $id;
		}

		return sprintf("%s_%s",
			$form->class,
			str_replace(array('.', '/'), '', $form->getName())
		);
	}

	/**
	 * @param FormField
	 *
	 * @return string
	 */
	public function generateFieldHolderID($field) {
		return $field->getName();
	}

	/**
	 * @param FormField
	 *
	 * @return string
	 */
	public function generateFieldID($field) {
		$name = preg_replace(
			'/(^-)|(-$)/', '',
			preg_replace('/[^A-Za-z0-9_-]+/', '-', $field->getName())
		);

		if($form = $field->getForm()) {
			$form = sprintf("%s_%s",
				get_class($form),
				str_replace(array('.', '/'), '', $form->getName())
			);

			return $form . '_' . $name;
		}

		return $name;
	}
}