function validTextField(field)
{
	if (field.value == null || field.value == "") { return false; }
	else { return true; }
}

function validEmailField(field)
{
	var reg = /^([A-Za-z0-9_\-\.])+\@([A-Za-z0-9_\-\.])+\.([A-Za-z]{2,4})$/;
	
	if (field.value == null || reg.test(field.value) == false) { return false; }
	else { return true; }
}

function validSingleCheckboxField(field)
{
	if (field.checked != true) { return false; }
	else { return true; }
}

function validSelectField(field)
{
	if (field.selectedIndex == null || field.selectedIndex == '') { return false; }
	else { return true; }
}

function validCheckboxField(fieldNodes)
{
	for (var i=0;i<fieldNodes.length;i++) { if (fieldNodes[i].checked) { return true; } }
	
	return false;
}

function confirmPasswordField(field1, field2)
{
	if (field1.value != field2.value || !validTextField(field1) || !validTextField(field2)) { return false; }
	else { return true; }
}