//验证是否是空值
function isEmpty(s)
{
	if ((s==null)||(s.length==0)){return true;}
	else{return false;}
}
//校验是否全由数字组成
function isNumber(s)
{
	var patrn=/^[0-9]{1,20}$/;
	if (!patrn.exec(s)){return false;}
	else{return true;}
}
//校验登录名：只能输入5-20个以字母开头、可带数字、“_”、“.”的字串
function isValidValue(s)
{
	var patrn=/^[a-zA-Z]{1}([a-zA-Z0-9]|[._]){4,24}$/;
	if (!patrn.exec(s)){return false;}
	else{return true;}
}
//校验是否Email地址
function isEmail(s)
{
	var patrn=/\w+([-+.]\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*/;
	if (!patrn.exec(s)){return false;}
	else{return true;}
}
//校验普通电话、传真号码：可以“+”开头，除数字外，可含有“-”
function isTel(s)
{
//var patrn=/^[+]{0,1}(\d){1,3}[ ]?([-]?(\d){1,12})+$/;
var patrn=/^[+]{0,1}(\d){1,3}[ ]?([-]?((\d)|[ ]){1,12})+$/;
if (!patrn.exec(s)){return false;}
else{return true;}
}
//校验手机号码：必须以数字开头，除数字外，可含有“-”
function isMobil(s)
{
var patrn=/^[+]{0,1}(\d){1,3}[ ]?([-]?((\d)|[ ]){1,12})+$/;
if (!patrn.exec(s)){return false;}
else{return true;}
}
//校验邮政编码
function isPostalCode(s)
{
//var patrn=/^[a-zA-Z0-9]{3,12}$/;
var patrn=/^[a-zA-Z0-9 ]{3,12}$/;
if (!patrn.exec(s)){return false;}
else{return true;}
}
//验证IP地址
function isIP(s)
{
var patrn=/^[0-9.]{1,20}$/;
if (!patrn.exec(s)){return false;}
else{return true;}
}