FormBuilderProcessor::allowSavePageField() method      
Returns true if given value should be saved, false if not (for hooks)
Usage
$bool = $processor->allowSavePageField(Page $page, string $pageFieldName, string $formFieldName, string $value, array $entry);Arguments
| Name | Type(s) | Description | 
|---|---|---|
$page | Page | Page being saved  | 
$pageFieldName | string | Name of Page field being saved. Can also be "field.subfield"  | 
$formFieldName | string | Name of form field the value came from  | 
$value | string | Value of field  | 
$entry | array | The entire original entry data (in case you need anything from it)  | 
Return value
bool
Hooking $processor→allowSavePageField(…)
You can add your own hook events that are executed either before or after the $processor->allowSavePageField(…) method is executed. Examples of both are included below. A good place for hook code such as this is in your /site/ready.php file.
Hooking before
The 'before' hooks are called immediately before each $processor->allowSavePageField(…) method call is executed. This type of hook is especially useful for modifying arguments before they are sent to the method.
$this->addHookBefore('FormBuilderProcessor::allowSavePageField', function(HookEvent $event) {
  // Get the object the event occurred on, if needed
  $FormBuilderProcessor = $event->object;
  // Get values of arguments sent to hook (and optionally modify them)
  $page = $event->arguments(0);
  $pageFieldName = $event->arguments(1);
  $formFieldName = $event->arguments(2);
  $value = $event->arguments(3);
  $entry = $event->arguments(4);
  /* Your code here, perhaps modifying arguments */
  // Populate back arguments (if you have modified them)
  $event->arguments(0, $page);
  $event->arguments(1, $pageFieldName);
  $event->arguments(2, $formFieldName);
  $event->arguments(3, $value);
  $event->arguments(4, $entry);
});      Hooking after
The 'after' hooks are called immediately after each $processor->allowSavePageField(…) method call is executed. This type of hook is especially useful for modifying the value that was returned by the method call.
$this->addHookAfter('FormBuilderProcessor::allowSavePageField', function(HookEvent $event) {
  // Get the object the event occurred on, if needed
  $FormBuilderProcessor = $event->object;
  // An 'after' hook can retrieve and/or modify the return value
  $return = $event->return;
  // Get values of arguments sent to hook (if needed)
  $page = $event->arguments(0);
  $pageFieldName = $event->arguments(1);
  $formFieldName = $event->arguments(2);
  $value = $event->arguments(3);
  $entry = $event->arguments(4);
  /* Your code here, perhaps modifying the return value */
  // Populate back return value, if you have modified it
  $event->return = $return;
});      $processor methods and properties
API reference based on ProcessWire core version 3.0.252