function check (theform){
	if (theform.userName.value == "") {
		alert("用户名不为空！");
		theform.userName.focus();
		return false;
	}
	if (theform.userPass.value == ""){
		alert("请输入密码");
		theform.userPass.focus();
		return false;
	}
	return true;
}
function login(theform){
	if (check(theform)){
		theform.submit();
	}
}