# Biblioitems form — overview

Where the form lives and how MARC fields are built for create/edit.

---

## File locations

| What | Path |
|------|------|
| **Form view (create & edit)** | `public_html/themes/main/views/items/biblios/form.blade.php` |
| **Form CSS** | `public_html/themes/main/assets/biblioitems/biblioitem_form_styles.css` |
| **Form scripts** | In the same file as the form: `form.blade.php` |

---

## How MARC fields are built

MARC fields come from the **MARC21** class:

```php
MARC21::biblio_form($tagfields, $subfields, $biblio, 'biblio', 'biblioitem', null, $formMode)
```

- **Create vs edit:** The form supports both modes. In edit mode, `$biblio` carries biblioitem data and guide variables so the form can show existing values and hints.
- **Entry point:** `MARC21::biblio_form()` prepares the data and returns the view:
  - `public_html/themes/main/partials/marc/marc_form.blade.php`
- **Partials:** All MARC-related partials (fields, indicators, reference file, live preview, etc.) live in:
  - `public_html/themes/main/partials/marc/`
  - `marc_form.blade.php` includes these partials as needed.