RSForm check if email is in database before submitting form

Question

I have an RSForm which has the following fields:

• Full Name
• Email Address

I only want to capture new data, how can I use the $_POST script to check if the email address submitted is already in the database?

According to the RSForms documentation I can do this using

$_POST['form']['email_address']

but I'm not really sure what code to use.

Answer 1

You need to enter the following into the 2nd textarea in the form properties tab under "PHP Scripts":

$formId = 0; // CHANGE THIS VALUE to your form ID

$db = JFactory::getDbo();
$query = $db->getQuery();

$query
    ->select("*")
    ->from("__rsform_submission_values")
    ->where("FormId = " . $db->q($formId))
    ->where("FieldValue = " . $db->q($_POST['form']['email_address'] ));

$db->setQuery($query);
$db->execute();

$num_rows = $db->getNumRows();

// We found this email in the submissions
if ($num_rows > 0) {
    $invalid[] = RSresolveComponentName('email_address', $formId);
    echo RSshowForm($formId, $_POST['form'], $invalid);
}

You could also create a new validation rule by adding this function to this file: components/com_rsform/controller/validation.php, which can be selected by editing the email_address field and selecting "unique" as the Validation Rule.

function unique($param, $extra=null)
{        
    $db = JFactory::getDBO();
    $param = $db->getEscaped($param);
    $db->setQuery("SELECT * FROM #__rsform_submission_values WHERE `FieldName`='email_address' AND `FieldValue`='".$param."'");
    $db->query();
    $invalid = $db->getNumRows();
    
    if ($invalid)
        return false;

    return true;
}

There is a little more documentation on custom validations on this page. https://www.rsjoomla.com/support/documentation/rsform-pro/customizing-rsform-pro/custom-validation-rules.html

This thread might also prove helpful: https://www.rsjoomla.com/forum/37-rsform-pro/9162-setup-form-so-each-user-can-only-submit-once-.html

EDIT:

This answer is old and most likely obsolete, I no longer do Joomla development.

Answer 2

Some things have changed in later versions of Joomla and RSForms over the past 6 years. As such @Helge Sverre's code is close but needs some modifications to work now.

• The "Script called on form display" checks to see if the error status is true, and if it is, it displays an error message. You can customise that to your liking.
• The "Script called on form process" is where the validation takes place. It loads the existing values for the email field from the database, then checks for a match. If there is a match, then it sets the error status to true and the validation status to false.
• This combination then reloads the form, with the validation = false stopping the submission, and the error code triggering the error message to show.

Script called on form display

if  ($_POST['form']['error'] == true) {
    // Modify message 
    $formLayout = "<div class='alert'>
                      <h3>You have already submitted this form using this email address.</h3>
                   </div>" . $formLayout;
}

Script called on form process

$formId = 0; // Change this value to your form ID
$_POST['form']['error'] = false;

$db = JFactory::getDbo();
$query = $db->getQuery(true);
    
$query
    ->select(array('*'))
    ->from($db->quoteName('#__rsform_submission_values'))
    ->where($db->quoteName('FormId') . ' = '. $db->quote($formId))
    ->where($db->quoteName("FieldValue") . " = " . $db->quote($_POST['form']['email'] )
);
// Check fieldname 'email' above is an exact case match for the field you are validating
    
$db->setQuery($query);
$result = $db->execute();
    
$num_rows = $db->getNumRows();
    
// We found this email in the submissions
if ($num_rows > 0) {
   // Invalidate the submit button, as it doesn't have a validation message
   $invalid[] = RSFormProHelper::getComponentId("Submit");
   // Set a variable in the $_POST['form'] array to flag error
   $_POST['form']['error'] = true;
}

In the code examples above, there's some critical things you need to update to specifically match what is in your form.

• Change the FormId value from 0 to match your form ID.
• Check email is the name of the field being validated (you might have 'email_address', 'Email' or 'Email Address' as variations that would break the code).
• Check Submit is the name of your submit button as that's the field this is invalidating, so needs to have a match to load in the $invalid array correctly.
• In the use case that saw this be rewritten, we emptied the Error Message for the form.