Editing Variable-Length Line Item Edits (section)

== Markup ==

=== Cross-site request forgery ===

* A CSRF token is created and saved as a session variable.
* The value of this variable is saved in a hidden element on the page: `#csrf-token` where it will then be available in jQuery.

=== Line item listings ===

* Outer container has `.line-items-container` class. 
** This element does not get modified by jQuery.
** The class is used as a selector in jQuery to target the parent of the individual line items.
* Each individual line item element has `.line-item` class. 
** The class name is used as a selector in jQuery to assign edit handlers to the individual line items.
** When iterating through the line item objects in PHP, they should be rendered using a separate PHP include file. This way, that line item include file can be shared between the front-end PHP template and the AJAX script that updates page content.
** The `.line-item` element must have the following attributes defined:
*** `data-id`: Record id of the line item in the database.
*** `data-type`: PHP class name of the object that can fetch and save the line item data to and from the database. 
* New item button:<syntaxhighlight lang="html4strict" enclose="div">
<button class="add-line-btn" data-pid="[PARENT_RECORD_ID]" data-type="[CONTENT_PHP_CLASS_NAME]" title="add new [OBJECT NAME]">add new [OBJECT_NAME]</button>
</syntaxhighlight>

=== Edit form ===

* The edit form markup will include the `.line-item` element. 
* The flattened display of the line item will be replaced in its entirety with the edit form markup.
* The edit form will be replaced in its entirety with the updated flattened display of the line item once editing has been completed.
* The edit form will include the following variables as hidden form elements:
** `class`: Name of PHP class that handles line item edits.
** `id`: Line item record id, if editing an existing line item record.
** `pid`: The record id of the parent record that the line item is linked to, if editing a new line item record.*