How to add a function to a text field?

• axixtix

• August 17, 2022 at 6:29 pm

I am using this code to add a validation of the letter of the Spanish D.N.I, but I don’t know why it doesn’t work for me. In case someone can help me.

add_action('acf/render_field_settings/type=textarea', 'validar_dni');
function validar_dni($dni){
 $letra = substr($dni, -1);
	$numeros = substr($dni, 0, -1);
	if ( substr("TRWAGMYFPDXBNJZSQVHLCKE", $numeros%23, 1) == $letra && strlen($letra) == 1 && strlen ($numeros) == 8 ){
		echo 'valido';
	}else{
		echo 'no valido';
	}
}

• John Huebner

• August 24, 2022 at 1:07 pm

acf/render_field_settings is used to add settings and not to perform an operation.

What is it you’re trying to achive? If you are attempting to validate a value then you need to use the acf/validate_value filter.