Gravity Form Custom Parameters...

functions.php

/*
	Make a hidden field, make it dynamic, give it the value of $parameter.	
	@usage: gform_field_value_$parameter
	
		1) Ask what month is it.
		2) Return a price depending on where the month sits.
	
	These are the parameters that I want to use:
	
		trackadult - Track Adult Prices
		trackchild - Track Under 16s
		
		roadadult - Road Adults
		roadchild - Road Child
		roadfamily - Road family
		roadcoach - Road Associate and Coaches
		roadsecond - Road Second Claim Member?
*/

/* Hidden Track - Adult Price Parameter */
add_filter("gform_field_value_trackadult", "meat_trackadult");
function meat_trackadult( $value ){
	$month = date('m');	
		if($month >='04' && $month <='06'): return '90';
	elseif($month >='07' && $month <='09'): return '68';
	elseif($month >='10' && $month <='12'): return '45';
	elseif($month >='01' && $month <='03'): return '23';
	else : return '90';
	endif;
}

/* Hidden Track - Child Price Parameter */
add_filter("gform_field_value_trackchild", "meat_trackchild");
function meat_trackchild( $value ){
	$month = date('m');	
		if($month >='04' && $month <='06'): return '65';
	elseif($month >='07' && $month <='09'): return '49';
	elseif($month >='10' && $month <='12'): return '33';
	elseif($month >='01' && $month <='03'): return '16';
	else : return '65';
	endif;
}

/* Hidden Road - Adult Price Parameter */
add_filter("gform_field_value_roadadult", "meat_roadadult");
function meat_roadadult( $value ){
	$month = date('m');	
		if($month >='04' && $month <='06'): return '65';
	elseif($month >='07' && $month <='09'): return '49';
	elseif($month >='10' && $month <='12'): return '33';
	elseif($month >='01' && $month <='03'): return '16';
	else : return '65';
	endif;
}

/* Hidden Road - Child Price Parameter */
add_filter("gform_field_value_roadchild", "meat_roadchild");
function meat_roadchild( $value ){
	$month = date('m');	
		if($month >='04' && $month <='06'): return '40';
	elseif($month >='07' && $month <='09'): return '30';
	elseif($month >='10' && $month <='12'): return '20';
	elseif($month >='01' && $month <='03'): return '10';
	else : return '40';
	endif;
}

/* Hidden Road - Family Price Parameter */
add_filter("gform_field_value_roadfamily", "meat_roadfamily");
function meat_roadfamily( $value ){
	$month = date('m');	
		if($month >='04' && $month <='06'): return '180';
	elseif($month >='07' && $month <='09'): return '135';
	elseif($month >='10' && $month <='12'): return '90';
	elseif($month >='01' && $month <='03'): return '45';
	else : return '180';
	endif;
}


/* Hidden Road - Coach Price Parameter */
add_filter("gform_field_value_roadcoach", "meat_roadcoach");
function meat_roadcoach( $value ){
	$month = date('m');	
		if($month >='04' && $month <='06'): return '5';
	elseif($month >='07' && $month <='09'): return '5';
	elseif($month >='10' && $month <='12'): return '5';
	elseif($month >='01' && $month <='03'): return '5';
	else : return '5';
	endif;
}

/* Hidden Road - Second Claim Price Parameter */
add_filter("gform_field_value_roadsecond", "meat_roadsecond");
function meat_roadsecond( $value ){
	$month = date('m');	
		if($month >='04' && $month <='06'): return '50';
	elseif($month >='07' && $month <='09'): return '38';
	elseif($month >='10' && $month <='12'): return '25';
	elseif($month >='01' && $month <='03'): return '13';
	else : return '50';
	endif;
}