Gravity Forms Wordpress Date Picker Age Verification

Question

I am using Gravity Forms (1.8.9) and Wordpress (3.9.1)

I have a form field as a datepicker on my site, and I want to allow submissions only if the user is 21 or older to be able to submit the form.

I was originally using the following code. It only worked for a single form for a while, but then it stopped working completely: http://lanche86.com/gravity-forms-18-years-old-verification/

I would like to be able to use the same code on different forms. Help!

Answer 1

You can do something like this:

add_filter("gform_field_validation_1_1", "dob_validate", 10, 4);

function dob_validate($result, $value, $form, $field){
    //Check if dob field matches required age
    if ($result["is_valid"]){
        // this the minimum age requirement we are validating
        $minimum_age = 18;

        // calculate age in years like a human, not a computer, based on the same birth date every year
        $age = date('Y') - substr($value, 6, 4);
        if (strtotime(date('Y-m-d')) - strtotime(date('Y') . '-' . substr($value, 0, 2) . '-' . substr($value, 3, 2)) < 0) {
            $age--;
        }

        if( $age < $minimum_age ){
            $result["is_valid"] = false;
            $result["message"] = "Sorry, you must be at least $minimum_age years old. You're $age years old.";
        }
    }
    //Check if dob field is empty
    if(empty($value)){
        $result["is_valid"] = false;
        $result["message"] = "This field is required.";
    }
    return $result;
}

I'm using Gravity Forms 1.8.8 and latest Wordpress and works as desired. Screenshot:

You can also edit this according to form and field:

add_filter("gform_field_validation_1_1", "dob_validate", 10, 4);

Where gform_field_validation_1_1 is for form 1 and field 1. If your forms id is 8 and field number is 2, you can change it to gform_field_validation_8_2.

You can also add that same filter multiple times for multiple forms and fields without recreating the dob_validate function.

Answer 2

If anybody still needs to implement this, try this:

    add_filter( 'gform_field_validation_1_1', function ( $result, $value, $form, $field ) {
    if ( $result['is_valid'] ) {
        if ( is_array( $value ) ) {
            $value = array_values( $value );
        }
        $date_value = GFFormsModel::prepare_date( $field->dateFormat, $value );

        $today = new DateTime();
        $diff  = $today->diff( new DateTime( $date_value ) );
        $age   = $diff->y;

        if ( $age < 18 ) {
            $result['is_valid'] = false;
            $result['message']  = 'Underage';
        }
    }

    return $result;
}, 10, 4 );

It's on Gravity Forms Documentation: https://docs.gravityforms.com/gform_field_validation/#13-date-field-age-validation