Validate Gravity Forms standard multi-part Address field to check for a UK Valid Postcode

gforms_address_uk_postcode_validation

add_filter("gform_field_validation_[FORM_ID]_[FIELD_ID]", "uk_postcode_validation", 10, 4);

function uk_postcode_validation($result, $value, $form, $field){
    //address field will pass $value as an array with each of the elements as an item within the array, the key is the field id
    
	$postcode = $value["[FIELD_ID].5"];
	
	//the default regex is valid both with and without the space in the middle. 
	//to force the space, replace with the following:
	//'#^(GIR ?0AA|[A-PR-UWYZ]([0-9]{1,2}|([A-HK-Y][0-9]([0-9ABEHMNPRV-Y])?)|[0-9][A-HJKPS-UW]) [0-9][ABD-HJLNP-UW-Z]{2})$#'
	
	if(!(preg_match('#^(GIR ?0AA|[A-PR-UWYZ]([0-9]{1,2}|([A-HK-Y][0-9]([0-9ABEHMNPRV-Y])?)|[0-9][A-HJKPS-UW]) ?[0-9][ABD-HJLNP-UW-Z]{2})$#', $postcode))) {
		$result["is_valid"] = false;
		$result["message"] = "Please enter a valid postcode (including the space).";
	}

    return $result;
}

I'm not too sure if this is allowed so please excuse me if i'm commenting out of place!

Can someone please talk me through this dummy style. I really need this functionality on my gravity forms but I have no idea what the different parts mean and where to put this code. Ideally, I just want postcodes in the BA and BS areas.

Thank you,

Elliott

Hi dude,

Using this, and the validation is great, but doesn't seem to show any errors when a postcode isn't valid?

EDIT: Nevermind. Don't just copy and paste folks, we should know better by now