Form generation

  1. drupal
    1. 5

Functions to enable the processing and display of HTML forms.

Drupal uses these functions to achieve consistency in its form processing and presentation, while simplifying code and reducing the amount of HTML that must be explicitly generated by modules.

The drupal_get_form() function handles retrieving, processing, and displaying a rendered HTML form for modules automatically. For example:

<?php
// Display the user registration form.
$output = drupal_get_form('user_register');
?>

Forms can also be built and submitted programmatically without any user input using the drupal_execute() function.

For information on the format of the structured arrays used to define forms, and more detailed explanations of the Form API workflow, see the reference and the quickstart guide.

Functions & methods

NameDescription
checkboxes_valueHelper function to load value from default value for checkboxes.
date_validateValidates the date type to stop dates like February 30, 2006.
drupal_executeRetrieves a form using a form_id, populates it with $form_values, processes it, and returns any validation errors encountered. This function is the programmatic counterpart to drupal_get_form().
drupal_get_formRetrieves a form from a builder function, passes it on for processing, and renders the form or redirects to its destination as appropriate. In multi-step form scenarios, it handles properly processing the values using the previous step's form…
drupal_prepare_formPrepares a structured form array by adding required elements, executing any hook_form_alter functions, and optionally inserting a validation token to prevent tampering.
drupal_process_formThis function is the heart of form API. The form gets built, validated and in appropriate cases, submitted.
drupal_redirect_formRedirect the user to a URL after a form has been processed.
drupal_render_formRenders a structured form array into themed HTML.
drupal_retrieve_formRetrieves the structured array that defines a given form.
drupal_submit_formProcesses user-submitted form data from a global variable using the submit functions defined in a structured form array.
drupal_validate_formValidates user-submitted form data from a global variable using the validate functions defined in a structured form array.
expand_checkboxes
expand_dateRoll out a single date element.
expand_password_confirmExpand a password_confirm field into two text boxes.
expand_radiosRoll out a single radios element to a list of radios, using the options array as index.
form_builderAdds some required properties to each form element, which are used internally in the form API. This function also automatically assigns the value property from the $edit array, provided the element doesn't already have an assigned value.
form_clean_idRemove invalid characters from an HTML ID attribute string.
form_errorFlag an element as having an error.
form_get_errorReturn the error message filed against the form with the specified name.
form_get_errorsReturn an associative array of all errors.
form_get_optionsTraverses a select element's #option array looking for any values that hold the given key. Returns an array of indexes that match.
form_options_flatten
form_select_options
form_set_errorFile an error against a form element. If the name of the element is edit[foo][bar] then you may pass either foo or foo][bar as $name foo will set an error for all its children.
form_set_valueUse this function to make changes to form values in the form validate phase, so they will be available in the submit phase in $form_values.
map_monthHelper function for usage with drupal_map_assoc to display month names.
password_confirm_validateValidate password_confirm element.
process_weightExpand weight elements into selects.
theme_button
theme_checkboxFormat a checkbox.
theme_checkboxesFormat a set of checkboxes.
theme_dateFormat a date selection element.
theme_fieldsetFormat a group of form items.
theme_fileFormat a file upload field.
theme_formFormat a form.
theme_form_elementReturn a themed form element.
theme_hiddenFormat a hidden form field.
theme_itemFormat a form item.
theme_markup
theme_passwordFormat a password field. *
theme_password_confirmFormat a password_confirm item.
theme_radioFormat a radio button.
theme_radiosFormat a set of radio buttons.
theme_selectFormat a dropdown menu or scrolling selection box.
theme_submit
theme_textareaFormat a textarea.
theme_textfieldFormat a textfield.
theme_token
weight_valueIf no default value is set for weight select boxes, use 0.
_drupal_clean_form_sessionsRemove form information that's at least a day old from the $_SESSION['form'] array.
_element_infoRetrieve the default properties for the defined element type.
_form_set_classSets a form element's class attribute.
_form_set_valueHelper function for form_set_value().
_form_validatePerforms validation on form elements. First ensures required fields are completed, #maxlength is not exceeded, and selected options were in the list of options given to the user. Then calls user-defined validators.

includes/form.inc, line 3