var currentLayer = 'div_1';
function showLayer(lyr,error_check_on) {
	if(error_check_on == 'Y') {
		var part_nr = lyr.slice(4)-1;
		var error = error_check_part(part_nr);
	} else {
		var error = false;
	}
	if(error == false) {
	   hideLayer(currentLayer);
	   document.getElementById(lyr).style.display = 'block';
	   currentLayer = lyr;
	   window.location.hash = "top";
	}
}
function hideLayer(lyr) {
   document.getElementById(lyr).style.display = 'none';
}
function error_check_part(i) {
	var error	=	false;
	var nrRegxp = /^[+]?\d*$/;

	if(document.getElementById('form_ihf_hmtlidnummer_'+i).value=='' || !nrRegxp.test(document.getElementById('form_ihf_hmtlidnummer_'+i).value)) {
	   document.getElementById('form_ihf_hmtlidnummer_'+i).className = 'error_red';
	   error = true;
	} else {
	   document.getElementById('form_ihf_hmtlidnummer_'+i).className = '';
	}
	if(document.getElementById('form_ihf_voornaam_'+i).value=='') {
	   document.getElementById('form_ihf_voornaam_'+i).className = 'error_red';
	   error = true;
	} else {
	   document.getElementById('form_ihf_voornaam_'+i).className = '';
	}
	if(document.getElementById('form_ihf_achternaam_'+i).value=='') {
	   document.getElementById('form_ihf_achternaam_'+i).className = 'error_red';
	   error = true;
	} else {
	   document.getElementById('form_ihf_achternaam_'+i).className = '';
	}
	if(document.getElementById('form_ihf_adres_'+i).value=='') {
	   document.getElementById('form_ihf_adres_'+i).className = 'error_red';
	   error = true;
	} else {
	   document.getElementById('form_ihf_adres_'+i).className = '';
	}
	if(document.getElementById('form_ihf_postcode_'+i).value=='') {
	   document.getElementById('form_ihf_postcode_'+i).className = 'error_red';
	   error = true;
	} else {
	   document.getElementById('form_ihf_postcode_'+i).className = '';
	}
	if(document.getElementById('form_ihf_plaats_'+i).value=='') {
	   document.getElementById('form_ihf_plaats_'+i).className = 'error_red';
	   error = true;
	} else {
	   document.getElementById('form_ihf_plaats_'+i).className = '';
	}
	if(document.getElementById('form_ihf_telefoonnummer_'+i).value=='') {
	   document.getElementById('form_ihf_telefoonnummer_'+i).className = 'error_red';
	   error = true;
	} else {
	   document.getElementById('form_ihf_telefoonnummer_'+i).className = '';
	}
	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(i==1) {
		if(document.getElementById('form_ihf_emailadres_'+i).value == '') {
		   document.getElementById('form_ihf_emailadres_'+i).className = 'error_red';
		   error = true;
		} else {
		   document.getElementById('form_ihf_emailadres_'+i).className = '';
		}
	} else {
		if(document.getElementById('form_ihf_emailadres_'+i).value != '' && !emailRegxp.test(document.getElementById('form_ihf_emailadres_'+i).value)) {
		   document.getElementById('form_ihf_emailadres_'+i).className = 'error_red';
		   error = true;
		} else {
		   document.getElementById('form_ihf_emailadres_'+i).className = '';
		}
	}
	if(error == true) {
		document.getElementById('form_ihf_error_div').style.display = 'block';
	} else {
		document.getElementById('form_ihf_error_div').style.display = 'none';
	}
	return error;
}