function clearText(thefield){
if (thefield.defaultValue==thefield.value)
thefield.value = ""
} 

// JavaScript Document
function close_gastenboek(this_div) {
	document.getElementById(this_div).style.display = 'none';
}
function open_gastenboek(this_div) {
	if(document.getElementById(this_div).style.display == 'block') {
		close_gastenboek(this_div);
	} else {
		document.getElementById(this_div).style.display = 'block';
	}
}
function error_check(this_div) {
	var error_mesg = '';
	var error_mesg1 = '';
	var error_mesg2 = '';
	var error_msg_tekst = new Array();
	var error_2 = 0;
	
if(this_div == 'gastenboek_toevoegen1') {	
	if(document.getElementById('naam').value=='' || document.getElementById('naam').value=='Naam' || document.getElementById('naam').value=='Vul hier je naam in.') {
	   error_mesg1 = 'Vul hier je naam in.';
	   error_mesg += '1';
	}
	if(document.getElementById('tekst').value == '' || document.getElementById('tekst').value=='Bericht' || document.getElementById('tekst').value=='Schrijf hier je bericht.') {
	   error_mesg2 = 'Schrijf hier je bericht.';
	   error_mesg += '1';
	}
	if(error_mesg != '') {
			if(error_mesg1!='') {
				document.getElementById('naam').value = error_mesg1;
			}
			if(error_mesg2!='') {
				document.getElementById('tekst').value = error_mesg2;
			}
	} else {
		submitForm(this_div);
	}
} else if (this_div == 'registratie') {
	if(document.getElementById('teamnaam').value=='' || document.getElementById('teamnaam').value=='Vul hier je teamnaam in.') {
	   error_2 += 1;
	   error_msg_tekst[error_2] = 'teamnaam';
	} else {
		document.getElementById('error_field_teamnaam').style.visibility = 'hidden';
	}
	var radio_choice_soort = false;
	for (counter = 0; counter < document.registratie.soort.length; counter++) {
		if (document.registratie.soort[counter].checked) {
			radio_choice_soort = true; 
		}
	}
	if(radio_choice_soort == false) {
	   error_2 += 1;
	   error_msg_tekst[error_2] = 'soort';
	} else {
		document.getElementById('error_field_soort').style.visibility = 'hidden';
	}
			
	if(document.getElementById('naam').value=='') {
	   error_2 += 1;
	   error_msg_tekst[error_2] = 'contactpersoon';
	} else {
		document.getElementById('error_field_contactpersoon').style.visibility = 'hidden';
	}
	if(document.getElementById('adres').value=='') {
	   error_2 += 1;
	   error_msg_tekst[error_2] = 'adres';
	} else {
		document.getElementById('error_field_adres').style.visibility = 'hidden';
	}
	if(document.getElementById('postcode').value=='' || document.getElementById('plaats').value=='') {
	   error_2 += 1;
	   error_msg_tekst[error_2] = 'adres';
	} else {
		document.getElementById('error_field_adres').style.visibility = 'hidden';
	}
	
	
	if(document.getElementById('email').value == '') {
	   		error_2 += 1;
	   		error_msg_tekst[error_2] = 'email';
			document.getElementById('error_field_email').innerHTML = '&nbsp;*';

	} else {
		var emailRegxp = /^([a-zA-Z0-9_\-])+(\.([a-zA-Z0-9_\-])+)*@((\[(((([0-1])?([0-9])?[0-9])|(2[0-4][0-9])|(2[0-5][0-5])))\.(((([0-1])?([0-9])?[0-9])|(2[0-4][0-9])|(2[0-5][0-5])))\.(((([0-1])?([0-9])?[0-9])|(2[0-4][0-9])|(2[0-5][0-5])))\.(((([0-1])?([0-9])?[0-9])|(2[0-4][0-9])|(2[0-5][0-5]))\]))|((([a-zA-Z0-9])+(([\-])+([a-zA-Z0-9])+)*\.)+([a-zA-Z])+(([\-])+([a-zA-Z0-9])+)*))$/;
	   	if(!emailRegxp.test(document.getElementById('email').value)) {
	   		error_2 += 1;
	   		error_msg_tekst[error_2] = 'email';
			document.getElementById('error_field_email').innerHTML = '&nbsp;Vul een geldig e-mail adres in!';
		} else {
			document.getElementById('error_field_email').style.visibility = 'hidden';
		}
	}

	if(document.getElementById('tel').value=='') {
	   error_2 += 1;
	   error_msg_tekst[error_2] = 'tel';
	} else {
		document.getElementById('error_field_tel').style.visibility = 'hidden';
	}

	if(error_2 > 0) {
	
		for(x in error_msg_tekst) {
		
			var error_field = 'error_field_'+error_msg_tekst[x];
			document.getElementById(error_field).style.visibility = 'visible';
		
		}
			document.getElementById('error_field_algemeen').style.visibility = 'visible';
	
	}else {
		submitForm(this_div);
	}

}

}
function submitForm(this_form) {
	document.getElementById(this_form).action = '';
	document.getElementById(this_form).submit();
}