function switchImg(theimg) {
	if (document.getElementById('mainpic')) {
		document.getElementById('mainpic').src=theimg;
	}
}


function formVal(thefields) {
	thereturn = true;
	thefparts = thefields.split(",");
	for (i=0; i<thefparts.length; i++) {
		if (document.getElementById(thefparts[i]).value=='' || document.getElementById(thefparts[i]).value=='your name' || document.getElementById(thefparts[i]).value=='your email address' || document.getElementById(thefparts[i]).value=='your telephone number') {
			document.getElementById(thefparts[i]).style.background='#ff0000';
			thereturn = false;
		}else{
			document.getElementById(thefparts[i]).style.background='#ffffff';
		}	
	}
	if (thereturn==false) { alert("Please complete all fields"); }
	return thereturn;
}