Fred

<?php$_POST['firstr'] = 'Fred';$_POST['lastr'] = 'Bloggs';//uncomment below to test$_POST['midr'] = 'bill';$valid = true;if(empty($_POST['firstr']) || empty($_POST['lastr'])){	$valid = false;}else{	$firstr = trim($_POST['firstr']);	$lastr = trim($_POST['lastr']);	if(!ctype_alpha($firstr) || !ctype_alpha($lastr))	{		$valid = false;	}	else	{		if(ctype_lower($firstr)) $firstr = ucfirst($firstr);		if(ctype_lower($lastr)) $lastr = ucfirst($lastr);		if(!preg_match('@^[A-Z][a-z]+$@', $firstr)) $valid = false;		if(!preg_match('@^[A-Z][a-z]+$@', $lastr)) $valid = false;		if(!empty($_POST['midr']))		{			$midr = trim($_POST['midr']);			if(!ctype_alpha($midr))			{				$valid = false;			}			else			{				if(ctype_lower($midr)) $midr = ucfirst($midr);				if(!preg_match('@^[A-Z][a-z]+$@', $midr)) $valid = false;			}		}		if(!empty($midr))		{			$fullname = $firstr.'_'.$midr.'_'.$lastr;		}		else		{			$fullname = $firstr.'_'.$lastr;			}	}	}if($valid){	echo $fullname;}else{	echo 'INVALID';}?>