function show_hide_block(a) {
	obj=document.getElementById(a);
	if (obj.style.display=='none') {
		obj.style.display='block';
	}else{
		obj.style.display='none';
		}
}
function checkEmptyString(field1) {
	var value1=field1.value.toString();
	value1=value1.replace(/(^\s*)|(\s*$)/g, "");
	if (value1 == "") {
		alert("Du har ikke fylt alle obligatoriske felt!");
		field1.focus();
		field1.select();
		field1.value=value1;
		return false;
	}
}
function checkEmail(email_field) {
	var email_string=email_field.value;
	var reMail;
	reMail = /^[0-9a-z]([-_.]?[0-9a-z])*@[0-9a-z]([-.]?[0-9a-z])*\.[a-z]{2,4}$/;

	if (!email_string.match(reMail)) {
		alert('Feil e-post adresse!');
		email_field.focus();
		email_field.select();
		return false;
	}
}