What Is Custom Scripting Per Field?

JCB allows you to assign custom PHP logic to individual fields at key lifecycle moments — such as when a value is loaded (get), saved (store), or rendered (shown in a form or list). This gives you field-level control over how data is processed and displayed, far beyond the standard Joomla field behavior.

You can define reusable scripts or write custom code directly in the field’s settings. This logic becomes part of your component’s compiled output and executes exactly where you need it.

Key Features

• 🧠 Save & Get Hooks: Define logic that runs:
  • Before saving the field value (onSave)
  • When retrieving the field value (onGet)
• 🖼️ Render Control: Modify how the field appears in:
  • Admin or Site edit forms
  • List/table views
  • Read-only or config-only displays
• 🔁 Multiple Contexts Supported: Apply logic in:
  • Admin edit view
  • Site view
  • Config view
  • Backend list/table view
• 💡 Conditional Logic: Add if/else, switch, or decisions based on user group, other field values, or context.
• 📦 Snippet Integration: Reference reusable Snippets or call shared helper functions.
• 🧪 Fully Compile-Time Controlled: Embedded directly into compiled field handlers — no post-compile editing required.
• 🔒 Safe & Isolated: Field scripting won’t affect other logic unless explicitly linked.

Common Use Cases

• Format a date/time value on load
• Auto-populate a field based on another field’s value
• Run validation or transformation before saving
• Show/hide fields conditionally at runtime
• Generate dynamic dropdown values from a helper method
• Encrypt or sanitize field input before storage

How to Use It

1. Go to Fields.
2. Select or create a field.
3. Find and select the “Custom Field” Field Type.
4. Add PHP code or use getOptions methods. Examples:

   // Get the databse object.
           $db = Factory::getDBO();
           $query = $db->getQuery(true);
           $query->select($db->quoteName(array('a.###ID###','a.###TEXT###'),array('###ID###')));
           $query->from($db->quoteName('###TABLE###', 'a'));
           $query->where($db->quoteName('a.published') . ' = 1');
           $query->order('a.###TEXT### ASC');
   

5. Save and build the component. The logic will be compiled into the field handler.

🧠 Pro Tip: Use insert/replace tags if you want the logic to remain editable directly in your IDE post-compile.

Conclusion

Custom scripting per field gives you surgical precision over field behavior — without needing to write full models or controllers. It’s an ideal way to enhance forms, enforce logic, and fine-tune data handling in a way that’s clean, reusable, and easy to maintain.