Error: Could not find a class derived from FM_ExtensionModule

Could not find a class derived from FM_ExtensionModule in this file Error extracting the module name from the file

The extension module should a PHP class derived from FM_ExtensionModule class. Then you can override the callbacks in your custom module.

Here is a sample extension module class:
{literal}

<?PHP
class MyCustomLoadingModule extends FM_ExtensionModule
{
    function BeforeFormDisplay(&$formvars)
    {
        $formvars["Name"] = "Default Name";
        return true;
    }
}
?>
    

Note that the MyCustomLoadingModule is derived from FM_ExtensionModule class.

For more information, go to Help->contents menu item in Simfatic Forms and search the index for 'extension module'