Gravity form disable past date for date field

<script>
gform.addFilter( 'gform_datepicker_options_pre_init', function( optionsObj, formId, fieldId ) {
    // Apply to field 2 only 
    if ( fieldId == 17 && formId == 4 ) {
        optionsObj.minDate = 0;
    }
    return optionsObj;
});
</script>