Using acf/validate_value to validate repeater field

• Jean-Philippe Côté

• December 11, 2014 at 6:15 am

I want to use acf/validate_value to make sure that a repeater field has at least one entry with its value set. However, the documentation doesn’t provide examples for the repeater field. How can I proceed ?

• James

• June 2, 2015 at 10:42 pm

Hi @jpcote

You can make use of the acf/validate_value filter to validate the value of the sub_fields within the repeater by hooking in to the filter using the $field_type.

You can try something like this:

add_filter('acf/validate_value/type={$field_type}', 'my_acf_validate_value', 10, 4);

function my_acf_validate_value( $valid, $value, $field, $input ){
	
	// bail early if value is already invalid
	if( !$valid ) {
		
		return $valid;
		
	}
}

• ituk

• September 23, 2016 at 9:09 pm

although this is old, for those who look for a good solution for this issue of validating the first row’s fields in a repeater, here is what I just figured out:

//validate first step
add_filter('acf/validate_value/key=field_57bc841e7f973', 'itamar_acf_validate_value__fs', 10, 4);
function itamar_acf_validate_value__fs( $valid, $value, $field, $input ){
	
	// bail early if value is already invalid
	if( !$valid ) {
		return $valid;
	}

 	// load data
	$repeater_field = $_POST['acf']['field_57bc841e7f973']; //repater parent key
	reset($repeater_field); //reset repeater array to the rist row
	$first_field = key($repeater_field); //get first key in the repeater array
	$my_text_field = $_POST['acf']['field_57bc841e7f973'][$first_field]['field_57bc8a5447d06']; //specific field
	$characters = mb_strlen($my_text_field, 'utf-8');
	if ( $characters < 100 ) {
		$valid = 'כתבת '.$characters.' תווים בלבד בתוכן השלב הראשון. עליך לכתוב לפחות 100 תווים.';
	} 
		
	// return
	return $valid; 
}

in this case the validation is for a specific field under the first row in a specific repeater. you can change the characters count to 1 and then you get a real “required” field.

• VisualHarmony

• March 1, 2017 at 2:29 pm

Thanks for sharing your code.

I may be mistaken, but I believe that I can add a simplification to ituk’s post. If you just want the first item in the repeater, you can target it with the [0] array index without needing to reset the repeater field. So the following chunk of ituk’s code:

$repeater_field = $_POST['acf']['field_57bc841e7f973']; //repater parent key
reset($repeater_field); //reset repeater array to the rist row
$first_field = key($repeater_field); //get first key in the repeater array
$my_text_field = $_POST['acf']['field_57bc841e7f973'][$first_field]['field_57bc8a5447d06']; //specific field

can be simplified to this:

$my_text_field = $_POST['acf']['field_57bc841e7f973'][0]['field_57bc8a5447d06']; //specific field

NOTE: This only works for the 1st item! It seems that the first item uses the [0] array index but each repeater subfield that gets added gets a randomly generated array index. So instead of going to [1] for the second item it will be something like [58b641f67f3de], which is a randomly generated string that is probably generated from the server’s timestamp.